January is one of the cooler months of the year in Irvine, with average highs near 18.3°C and lows around 9.4°C (mean 13.9°C). It is a relatively wet time of year, averaging 66 mm of rainfall and 63% relative humidity across the period.
January is one of the cooler months of the year in Irvine. Across 45 years of records, the warmest January in Irvine was 2003 — when the month averaged 17.4°C — while the coldest was 1982 at 11.7°C. Typical January days reach 18.3°C with nights near 9.4°C. The long-term trend is warming, about 0.3°C per decade.
January is a relatively wet time of year in Irvine, averaging 66 mm of rainfall. The wettest January on record was 1993 with 342 mm, while the driest was 2014 at 2 mm.
Relative humidity in Irvine during January averages 63%. The most humid January was 1995 at 81%, and the least humid was 2014 at 50%.
January receives about 3.2 kWh/m²/day of solar energy in Irvine. The sunniest January was 2006 at 3.6 kWh/m²/day, and the cloudiest were 1993 and 1995 at 2.6.
Average wind speed in Irvine during January is 2.2 m/s. The windiest January was 1993 at 3 m/s, while the calmest was 2015 at 1.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 13.3°C | 13.5°C | 13.9°C | 14.6°C | 14.1°C | +0.8°C |
| Avg High | 18.1°C | 17.8°C | 18.3°C | 19.0°C | 18.3°C | +0.2°C |
| Avg Low | 8.5°C | 9.3°C | 9.5°C | 10.2°C | 9.8°C | +1.3°C |
| Avg Rain | 48 mm | 108 mm | 52 mm | 65 mm | 49 mm | +1 mm |
January temperatures in Irvine have risen by about 0.7°C between 1981–1985 and 2021–2025.
January has ranged from a record low of 0.5°C (1987) to a record high of 29.6°C (2021).
Rainfall in January is a relatively wet time of year, averaging 66 mm, with a wettest year of 342 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 Irvine
If your dates are flexible, the more temperate months of July and September tend to be the most comfortable for visiting Irvine. That said, January — with days averaging 18.3°C and nights around 9.4°C (mean 13.9°C) and moderate rainfall (66 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 | 18.8°C | 14.1°C | 9.4°C | 25.9°C | 6.0°C | 15 mm | 55% | 2 m/s | 3.5 |
| 2024 | 17.9°C | 14.1°C | 10.2°C | 24.8°C | 4.8°C | 57 mm | 71% | 2 m/s | 3.2 |
| 2023 | 15.8°C | 12.4°C | 9.0°C | 20.3°C | 4.5°C | 165 mm | 75% | 2.6 m/s | 2.9 |
| 2022 | 19.4°C | 14.8°C | 10.2°C | 24.2°C | 5.1°C | 3 mm | 62% | 1.7 m/s | 3.3 |
| 2021 | 19.2°C | 14.5°C | 9.8°C | 29.6°C | 4.7°C | 46 mm | 61% | 2.1 m/s | 3.4 |
| 2020 | 18.6°C | 14.5°C | 10.3°C | 24.8°C | 8.2°C | 8 mm | 70% | 1.6 m/s | 3.4 |
| 2019 | 18.1°C | 14.1°C | 10.2°C | 24.6°C | 4.4°C | 112 mm | 69% | 2.2 m/s | 3.1 |
| 2018 | 21.4°C | 16.9°C | 12.3°C | 27.6°C | 6.6°C | 53 mm | 57% | 1.7 m/s | 3.3 |
| 2017 | 16.0°C | 12.6°C | 9.1°C | 23.1°C | 4.7°C | 163 mm | 75% | 2.5 m/s | 2.9 |
| 2016 | 17.3°C | 13.5°C | 9.7°C | 21.4°C | 6.0°C | 87 mm | 71% | 2.2 m/s | 2.9 |
| 2015 | 20.4°C | 15.9°C | 11.5°C | 25.9°C | 5.5°C | 24 mm | 61% | 1.5 m/s | 3.2 |
| 2014 | 22.0°C | 17.1°C | 12.2°C | 28.3°C | 8.9°C | 2 mm | 50% | 1.6 m/s | 3.4 |
| 2013 | 17.8°C | 12.8°C | 7.9°C | 24.3°C | 1.9°C | 30 mm | 54% | 2 m/s | 3.4 |
| 2012 | 20.1°C | 15.1°C | 10.1°C | 27.2°C | 5.5°C | 19 mm | 55% | 1.7 m/s | 3.4 |
| 2011 | 18.5°C | 14.0°C | 9.4°C | 25.4°C | 3.3°C | 18 mm | 62% | 1.7 m/s | 3.4 |
| 2010 | 18.6°C | 14.3°C | 10.0°C | 23.8°C | 5.4°C | 140 mm | 66% | 2.2 m/s | 3 |
| 2009 | 20.4°C | 15.4°C | 10.3°C | 27.4°C | 4.5°C | 5 mm | 56% | 1.9 m/s | 3.4 |
| 2008 | 16.0°C | 12.1°C | 8.2°C | 22.8°C | 4.7°C | 142 mm | 69% | 2.8 m/s | 3 |
| 2007 | 17.0°C | 12.2°C | 7.4°C | 27.5°C | 1.6°C | 14 mm | 55% | 2.3 m/s | 3.4 |
| 2006 | 18.7°C | 14.0°C | 9.4°C | 28.0°C | 4.7°C | 30 mm | 61% | 2.3 m/s | 3.6 |
| 2005 | 17.3°C | 13.7°C | 10.2°C | 25.7°C | 6.6°C | 204 mm | 74% | 2.3 m/s | 2.9 |
| 2004 | 18.2°C | 13.9°C | 9.6°C | 24.7°C | 6.0°C | 10 mm | 63% | 1.8 m/s | 3.4 |
| 2003 🔥 | 22.4°C | 17.4°C | 12.4°C | 29.5°C | 7.0°C | 3 mm | 57% | 1.7 m/s | 3.4 |
| 2002 | 17.8°C | 13.2°C | 8.6°C | 25.0°C | 1.7°C | 12 mm | 60% | 1.9 m/s | 3.3 |
| 2001 | 16.5°C | 12.5°C | 8.5°C | 25.3°C | 3.9°C | 74 mm | 63% | 2 m/s | 3.1 |
| 2000 | 18.5°C | 14.4°C | 10.2°C | 25.2°C | 6.2°C | 22 mm | 68% | 1.9 m/s | 3.1 |
| 1999 | 18.5°C | 14.0°C | 9.6°C | 24.9°C | 4.6°C | 33 mm | 64% | 1.9 m/s | 3.2 |
| 1998 | 17.7°C | 14.0°C | 10.4°C | 22.4°C | 6.4°C | 74 mm | 73% | 1.9 m/s | 3 |
| 1997 | 16.9°C | 13.2°C | 9.5°C | 23.2°C | 4.1°C | 119 mm | 75% | 2.6 m/s | 2.8 |
| 1996 | 18.7°C | 14.1°C | 9.6°C | 26.1°C | 4.6°C | 65 mm | 63% | 2.2 m/s | 3.1 |
| 1995 | 15.5°C | 12.3°C | 9.1°C | 22.8°C | 4.6°C | 270 mm | 81% | 2.8 m/s | 2.6 |
| 1994 | 19.9°C | 14.8°C | 9.7°C | 25.3°C | 5.6°C | 21 mm | 51% | 2 m/s | 3.5 |
| 1993 🌧️ | 15.8°C | 12.4°C | 9.1°C | 21.4°C | 3.2°C | 342 mm | 76% | 3 m/s | 2.6 |
| 1992 | 18.9°C | 13.7°C | 8.5°C | 25.2°C | 4.2°C | 58 mm | 56% | 2.5 m/s | 3.3 |
| 1991 | 18.1°C | 13.3°C | 8.5°C | 25.4°C | 5.6°C | 33 mm | 61% | 1.9 m/s | 3.3 |
| 1990 | 18.3°C | 13.4°C | 8.5°C | 25.2°C | 4.0°C | 64 mm | 60% | 2.4 m/s | 3.4 |
| 1989 | 17.0°C | 11.8°C | 6.6°C | 24.4°C | 2.2°C | 21 mm | 57% | 2.5 m/s | 3.3 |
| 1988 | 17.3°C | 12.6°C | 8.0°C | 23.1°C | 1.4°C | 55 mm | 62% | 2.5 m/s | 3 |
| 1987 | 17.5°C | 12.5°C | 7.5°C | 25.5°C | 0.5°C | 52 mm | 59% | 2.5 m/s | 3.2 |
| 1986 | 20.9°C | 15.9°C | 11.0°C | 26.8°C | 7.8°C | 38 mm | 64% | 1.9 m/s | 3 |
| 1985 | 16.4°C | 11.8°C | 7.2°C | 20.3°C | 1.6°C | 26 mm | 65% | 2.4 m/s | 3.2 |
| 1984 | 19.4°C | 14.3°C | 9.2°C | 24.4°C | 5.6°C | 5 mm | 58% | 2.5 m/s | 3.2 |
| 1983 | 18.7°C | 14.2°C | 9.6°C | 25.1°C | 5.0°C | 88 mm | 63% | 2.4 m/s | — |
| 1982 ❄️ | 16.4°C | 11.7°C | 6.9°C | 22.6°C | 1.6°C | 98 mm | 62% | 2.8 m/s | — |
| 1981 | 19.1°C | 14.7°C | 10.2°C | 24.9°C | 2.3°C | 46 mm | 59% | 2.1 m/s | — |
Actual recorded January data for each year, 1981–2025 — sourced from NASA POWER.
The average high in January is around 18.3°C with lows near 9.4°C (mean 13.9°C), based on 45 years of NASA POWER data.
January averages 66 mm of rainfall in Irvine, a relatively wet time of year. The wettest on record was 342 mm in 1993.
The hottest January reached 29.6°C in 2021. The coldest dipped to 0.5°C in 1987.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 0.7°C. Daytime highs moved from 18°C to 18.2°C and overnight lows from 8.6°C to 9.7°C over the same span.
January is one of the cooler months of the year in Irvine and a relatively wet time of year, so plan for around 18.3°C daytime highs and 9.4°C at night.
Yes — January is the coldest month of the year in Irvine, averaging 13.9°C.
For January in Irvine, pack light layers you can adjust through the day, with typical highs of 18.3°C and lows of 9.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in January averages 63% — moderately humid.
Average wind speed in January is 2.2 m/s. The windiest January on record averaged 3 m/s (1993).
The wettest January on record was 1993 with 342 mm. On average, January sees 66 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 Irvine behaves each January, 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 January specifically, along with year-by-year records and how the month has changed over the decades.
