Climate averages 1991–2020
Irvine weather
by month.
See how the year changes. August has the highest average daily maximum; August has the lowest average monthly rainfall.
Pleasant-weather months by our simple rule: JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
Long-term climate patterns, not a forecast for a particular trip.
Across the year Irvine averages a daytime high of 22.6°C and a nighttime low of 13.3°C, with about 364 mm of rain on roughly 35 days. August is the warmest month (average high 28.2°C) and December the coolest (18.2°C). February is the wettest month with 92 mm; August is the driest with under 1 mm.
Months with pleasant weather by a simple rule (average high between 18°C and 29°C, average low of at least 5°C and at most 8 rain days): January, February, March, April, May, June, July, August, September, October, November and December. This looks at temperature and rain only, not humidity, wind, sea temperature or crowds.
The annual picture
A year in Irvine
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Irvine climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 18.3°C8.4°C | 8.4°C | 79 | 5.7 | 10.210 h |
| February | 18.3°C9.1°C | 9.1°C | 92 | 6.4 | 11.011 h |
| March | 19.3°C10.4°C | 10.4°C | 56 | 6.0 | 12.012 h |
| April | 20.7°C11.8°C | 11.8°C | 23 | 3.1 | 13.013 h |
| May | 22.1°C13.8°C | 13.8°C | 9.3 | 1.7 | 13.914 h |
| June | 24.4°C15.7°C | 15.7°C | 2.0 | 0.3 | 14.314 h |
| July | 27.1°C18.0°C | 18.0°C | 1.6 | 0.5 | 14.214 h |
| August | 28.2°C18.9°C | 18.9°C | 0.9 | 0.2 | 13.413 h |
| September | 27.6°C18.3°C | 18.3°C | 4.3 | 0.8 | 12.412 h |
| October | 24.9°C15.4°C | 15.4°C | 17 | 2.2 | 11.411 h |
| November | 21.6°C11.6°C | 11.6°C | 24 | 2.6 | 10.510 h |
| December | 18.2°C8.4°C | 8.4°C | 55 | 5.0 | 10.010 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
Nearby cities
- Santa Ana, United StatesUnited States · 9 kmHigh 21.4°C · Low 12.9°C · 364 mm rain a year
- Mission ViejoUnited States · 16 kmHigh 21.7°C · Low 13.1°C · 309 mm rain a year
- Huntington BeachUnited States · 16 kmHigh 21.3°C · Low 13.0°C · 310 mm rain a year
- Westminster (California), United StatesUnited States · 20 kmHigh 22.7°C · Low 12.4°C · 310 mm rain a year
- AnaheimUnited States · 20 kmHigh 22.9°C · Low 12.2°C · 310 mm rain a year
- FullertonUnited States · 24 kmHigh 24.3°C · Low 12.4°C · 310 mm rain a year
- Buena ParkUnited States · 27 kmHigh 24.1°C · Low 12.3°C · 310 mm rain a year
- CoronaUnited States · 33 kmHigh 24.8°C · Low 12.0°C · 454 mm rain a year
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsWhat do the high and low temperatures mean?
We average the daily maximum and daily minimum for each calendar month over 1991–2020. They are not record extremes, a forecast range or temperatures at a fixed time of day.
How is a rain day counted?
A local calendar day (standard time, UTC-8, no daylight saving) with at least 1 mm of total precipitation counts as one rain day. We count these for each year and month, then average across 30 years. The average does not predict which days will be wet.
Where do the numbers come from?
ERA5-Land (temperature) and ERA5 (precipitation) reanalysis from the Copernicus Climate Change Service, read from the Open-Meteo open-data archive. Temperature comes from the 0.1° model cell at 33.70°, -117.80° (4 km from the city centre), adjusted up by 0.5°C for the difference between the city's elevation (22 m) and the cell's (97 m). Rain comes from the 0.25° cell at 33.75°, -117.75°. Santa Ana, United States lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells. These are model estimates, not weather-station readings; coast, hills and city streets can differ.
Does this page show sunshine, humidity or sea temperature?
No. The data used here contain air temperature and precipitation only. Daylight hours are calculated from the city's latitude (sunrise to sunset), not measured sunshine.