December is one of the cooler months of the year in Chula Vista, with average highs near 17.7°C and lows around 8.6°C (mean 13.2°C). It is a relatively wet time of year, averaging 43 mm of rainfall and 63% relative humidity across the period.
December is one of the cooler months of the year in Chula Vista. Across 45 years of records, the warmest December in Chula Vista was 2025 — when the month averaged 16.5°C — while the coldest was 1987 at 10.7°C. Typical December days reach 17.7°C with nights near 8.6°C. The long-term trend is warming, about 0.4°C per decade.
December is a relatively wet time of year in Chula Vista, averaging 43 mm of rainfall. The wettest December on record was 2016 with 126 mm, while the driest was 2024 at 1 mm.
Relative humidity in Chula Vista during December averages 63%. The most humid Decembers were 2012 and 2021 at 73%, and the least humid was 2017 at 42%.
December receives about 2.9 kWh/m²/day of solar energy in Chula Vista. The sunniest Decembers were 1999, 2006 and 2017 at 3.3 kWh/m²/day, and the cloudiest were 2010 and 2021 at 2.5.
Average wind speed in Chula Vista during December is 2.5 m/s. The windiest December was 1990 at 3.6 m/s, while the calmest was 2024 at 1.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 12.8°C | 12.6°C | 12.9°C | 13.4°C | 14.5°C | +1.7°C |
| Avg High | 17.4°C | 17.3°C | 17.4°C | 17.8°C | 19.1°C | +1.7°C |
| Avg Low | 8.1°C | 8.0°C | 8.3°C | 9.0°C | 9.9°C | +1.8°C |
| Avg Rain | 48 mm | 27 mm | 39 mm | 62 mm | 35 mm | -14 mm |
December temperatures in Chula Vista have risen by about 1.7°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -1°C (1990) to a record high of 27.5°C (2025).
Rainfall in December is a relatively wet time of year, averaging 43 mm, with a wettest year of 126 mm.
A quieter season to visit Chula Vista
If your dates are flexible, the more temperate months of July and September tend to be the most comfortable for visiting Chula Vista. That said, December — with days averaging 17.7°C and nights around 8.6°C (mean 13.2°C) and moderate rainfall (43 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 🔥 | 21.3°C | 16.5°C | 11.7°C | 27.5°C | 7.4°C | 35 mm | 62% | 2.1 m/s | — |
| 2024 | 20.4°C | 15.5°C | 10.5°C | 25.8°C | 8.0°C | 1 mm | 60% | 1.7 m/s | 2.7 |
| 2023 | 19.8°C | 15.1°C | 10.4°C | 24.8°C | 7.7°C | 17 mm | 66% | 2 m/s | 3 |
| 2022 | 17.2°C | 13.0°C | 8.8°C | 25.7°C | 4.4°C | 40 mm | 71% | 2 m/s | 2.8 |
| 2021 | 16.8°C | 12.9°C | 8.9°C | 27.4°C | 5.8°C | 97 mm | 73% | 2.5 m/s | 2.5 |
| 2020 | 18.8°C | 14.0°C | 9.2°C | 25.0°C | 6.1°C | 17 mm | 53% | 2.5 m/s | 3 |
| 2019 | 16.4°C | 12.7°C | 8.9°C | 21.9°C | 4.5°C | 105 mm | 72% | 2.4 m/s | 2.7 |
| 2018 | 18.0°C | 13.6°C | 9.3°C | 23.7°C | 3.9°C | 58 mm | 69% | 2.1 m/s | 2.9 |
| 2017 | 21.5°C | 16.1°C | 10.7°C | 27.2°C | 4.9°C | 1 mm | 42% | 2.3 m/s | 3.3 |
| 2016 🌧️ | 17.4°C | 13.1°C | 8.9°C | 23.0°C | 3.6°C | 126 mm | 70% | 2.8 m/s | 2.8 |
| 2015 | 17.5°C | 12.7°C | 7.8°C | 26.2°C | 3.5°C | 43 mm | 61% | 2.7 m/s | 3.2 |
| 2014 | 17.9°C | 14.0°C | 10.2°C | 24.7°C | 4.3°C | 78 mm | 72% | 2.3 m/s | 2.8 |
| 2013 | 18.0°C | 13.2°C | 8.4°C | 25.1°C | 4.0°C | 13 mm | 57% | 2.6 m/s | 3.1 |
| 2012 | 16.9°C | 12.8°C | 8.6°C | 24.1°C | 3.3°C | 48 mm | 73% | 2.4 m/s | 2.7 |
| 2011 | 16.6°C | 11.9°C | 7.2°C | 24.7°C | 3.2°C | 29 mm | 61% | 2.1 m/s | 3.2 |
| 2010 | 17.4°C | 13.5°C | 9.5°C | 24.6°C | 4.0°C | 117 mm | 72% | 2.7 m/s | 2.5 |
| 2009 | 16.0°C | 11.9°C | 7.8°C | 22.9°C | 3.6°C | 72 mm | 68% | 2.6 m/s | 2.7 |
| 2008 | 16.1°C | 12.0°C | 7.9°C | 25.1°C | 1.8°C | 115 mm | 71% | 2.9 m/s | 2.6 |
| 2007 | 15.8°C | 11.3°C | 6.8°C | 24.4°C | 2.0°C | 24 mm | 64% | 3 m/s | 3.1 |
| 2006 | 18.5°C | 13.3°C | 8.0°C | 25.3°C | 3.8°C | 16 mm | 53% | 2.6 m/s | 3.3 |
| 2005 | 19.4°C | 14.6°C | 9.8°C | 25.6°C | 7.3°C | 2 mm | 60% | 1.9 m/s | 2.7 |
| 2004 | 17.2°C | 12.8°C | 8.4°C | 24.1°C | 2.6°C | 80 mm | 69% | 2.9 m/s | 2.9 |
| 2003 | 17.5°C | 12.8°C | 8.2°C | 22.5°C | 2.7°C | 21 mm | 63% | 2.5 m/s | 2.9 |
| 2002 | 16.9°C | 12.7°C | 8.6°C | 21.7°C | 4.1°C | 42 mm | 71% | 2.2 m/s | 3 |
| 2001 | 16.5°C | 12.0°C | 7.5°C | 21.8°C | 4.6°C | 18 mm | 67% | 2.6 m/s | 3.1 |
| 2000 | 20.2°C | 15.2°C | 10.3°C | 24.4°C | 7.8°C | 1 mm | 54% | 2.1 m/s | 2.9 |
| 1999 | 19.1°C | 13.9°C | 8.7°C | 25.3°C | 5.2°C | 6 mm | 48% | 2.7 m/s | 3.3 |
| 1998 | 16.9°C | 12.1°C | 7.3°C | 24.2°C | 2.6°C | 17 mm | 58% | 2.7 m/s | 3.1 |
| 1997 | 17.0°C | 12.5°C | 8.0°C | 23.8°C | 2.8°C | 50 mm | 61% | 3.2 m/s | 3.1 |
| 1996 | 17.8°C | 13.3°C | 8.7°C | 23.6°C | 5.3°C | 22 mm | 66% | 3.2 m/s | 2.7 |
| 1995 | 19.0°C | 14.2°C | 9.5°C | 24.7°C | 6.0°C | 9 mm | 68% | 2.1 m/s | 2.8 |
| 1994 | 16.8°C | 12.3°C | 7.9°C | 22.9°C | 4.0°C | 20 mm | 66% | 2.5 m/s | 2.8 |
| 1993 | 17.4°C | 12.6°C | 7.9°C | 23.3°C | 4.2°C | 15 mm | 59% | 3 m/s | 3.2 |
| 1992 | 15.5°C | 11.3°C | 7.0°C | 21.1°C | 1.7°C | 62 mm | 67% | 2.9 m/s | 2.8 |
| 1991 | 17.0°C | 12.7°C | 8.4°C | 20.7°C | 3.2°C | 46 mm | 66% | 2.5 m/s | 2.7 |
| 1990 | 16.0°C | 11.5°C | 7.0°C | 24.2°C | -1.0°C | 22 mm | 51% | 3.6 m/s | 3 |
| 1989 | 19.7°C | 14.5°C | 9.2°C | 26.1°C | 4.3°C | 8 mm | 49% | 2.8 m/s | 3 |
| 1988 | 16.6°C | 12.0°C | 7.4°C | 25.1°C | 0.8°C | 54 mm | 60% | 2.9 m/s | 3 |
| 1987 ❄️ | 15.2°C | 10.7°C | 6.2°C | 25.5°C | -0.4°C | 43 mm | 66% | 2.6 m/s | 2.8 |
| 1986 | 18.4°C | 13.5°C | 8.6°C | 24.2°C | 4.4°C | 20 mm | 59% | 2.2 m/s | 2.9 |
| 1985 | 17.5°C | 12.8°C | 8.1°C | 21.7°C | 2.2°C | 41 mm | 64% | 2.5 m/s | 2.8 |
| 1984 | 15.7°C | 11.4°C | 7.1°C | 19.5°C | 2.6°C | 122 mm | 72% | 2.7 m/s | 2.8 |
| 1983 | 17.0°C | 13.0°C | 9.0°C | 23.5°C | 4.6°C | 60 mm | 72% | 2.6 m/s | — |
| 1982 | 17.0°C | 12.3°C | 7.6°C | 23.5°C | 2.0°C | 62 mm | 64% | 3 m/s | — |
| 1981 | 19.8°C | 14.8°C | 9.9°C | 25.1°C | 5.3°C | 25 mm | 58% | 2.2 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 17.7°C with lows near 8.6°C (mean 13.2°C), based on 45 years of NASA POWER data.
December averages 43 mm of rainfall in Chula Vista, a relatively wet time of year. The wettest on record was 126 mm in 2016.
The hottest December reached 27.5°C in 2025. The coldest dipped to -1°C in 1990.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.7°C. Daytime highs moved from 17.4°C to 19.1°C and overnight lows from 8.3°C to 10.1°C over the same span.
December is one of the cooler months of the year in Chula Vista and a relatively wet time of year, so plan for around 17.7°C daytime highs and 8.6°C at night.
Not quite — December is the 2nd coolest month in Chula Vista, averaging 13.2°C.
For December in Chula Vista, pack light layers you can adjust through the day, with typical highs of 17.7°C and lows of 8.6°C.
Relative humidity in December averages 63% — moderately humid.
Average wind speed in December is 2.5 m/s. The windiest December on record averaged 3.6 m/s (1990).
The wettest December on record was 2016 with 126 mm. On average, December sees 43 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 Chula Vista 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.
