Irvine, CA Climate & Monthly Averages
The climate of Irvine
Weather in Irvine is shaped by its semi-arid climate - expect big day-to-night temperature swings and modest rainfall. August afternoons typically reach 83°F (28°C), while January highs hover near 65°F (18°C). Annual precipitation averages 14.6 inches (370 mm) over about 40 rainy days.
Climate quick facts
- Hottest month: August - highs near 83°F (28°C)
- Coldest month: January - highs near 65°F (18°C)
- Record high: 108°F (42°C) · Record low: 34°F (1°C) (2015–2024)
- Wettest month: January (6 rainy days) · Sunniest: July (13.4 h sun/day)
- Climate type: semi-arid - big day-to-night temperature swings and modest rainfall
Temperatures through the year
The warmest stretch of the year centers on August. Highs average 83°F (28°C) and overnight lows stay near 65°F (18°C). The coolest month is January, with typical highs of 65°F (18°C) and lows around 48°F (9°C). Based on 2015–2024 weather data, temperatures have reached as high as 108°F (42°C) and dropped as low as 34°F (1°C).
Rain, sun and snow
January is usually the wettest month. It brings about 3.1 inches (80 mm) of rain over 6 days, while July is the driest. July brings the most sunshine, averaging 13.4 hours of sun a day.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 65° | 48° | 6 | 3.1 in | 8.4 h/day | 69% |
| February | 66° | 48° | 6 | 2.6 in | 9.1 h/day | 65% |
| March | 67° | 50° | 8 | 2.4 in | 10.4 h/day | 72% |
| April | 71° | 54° | 4 | 0.8 in | 11.3 h/day | 70% |
| May | 71° | 56° | 3 | 0.6 in | 12.0 h/day | 74% |
| June | 77° | 60° | 1 | 0.2 in | 13.0 h/day | 73% |
| July | 81° | 64° | 0 | 0.1 in | 13.4 h/day | 74% |
| August | 83° | 65° | 1 | 0.3 in | 12.4 h/day | 74% |
| September | 82° | 64° | 2 | 0.4 in | 11.3 h/day | 73% |
| October | 79° | 60° | 2 | 0.5 in | 10.3 h/day | 68% |
| November | 72° | 53° | 2 | 0.8 in | 9.5 h/day | 60% |
| December | 66° | 48° | 5 | 2.5 in | 8.1 h/day | 66% |
Irvine month by month
Irvine weather in January
January brings highs around 65°F (18°C), lows near 48°F (9°C), about 6 wet days - typically the coldest month and the wettest month of the year in Irvine.
Irvine weather in February
February brings highs around 66°F (19°C), lows near 48°F (9°C), about 6 wet days.
Irvine weather in March
March brings highs around 67°F (19°C), lows near 50°F (10°C), about 8 wet days.
Irvine weather in April
April brings highs around 71°F (22°C), lows near 54°F (12°C), about 4 wet days.
Irvine weather in May
May brings highs around 71°F (22°C), lows near 56°F (13°C), about 3 wet days.
Irvine weather in June
June brings highs around 77°F (25°C), lows near 60°F (16°C), about 1 wet days.
Irvine weather in July
July brings highs around 81°F (27°C), lows near 64°F (18°C), about 0 wet days - typically the driest month and the sunniest month of the year in Irvine.
Irvine weather in August
August brings highs around 83°F (28°C), lows near 65°F (18°C), about 1 wet days - typically the hottest month of the year in Irvine.
Irvine weather in September
September brings highs around 82°F (28°C), lows near 64°F (18°C), about 2 wet days.
Irvine weather in October
October brings highs around 79°F (26°C), lows near 60°F (16°C), about 2 wet days.
Irvine weather in November
November brings highs around 72°F (22°C), lows near 53°F (12°C), about 2 wet days.
Irvine weather in December
December brings highs around 66°F (19°C), lows near 48°F (9°C), about 5 wet days.
Seasons in Irvine
Spring (March through May)
Spring in Irvine is pleasantly warm, with daytime highs averaging 70°F (21°C) and nights around 53°F (12°C); rain falls on about 15 days over the three months.
Summer (June through August)
Summer in Irvine is mild and warm, with daytime highs averaging 80°F (27°C) and nights around 63°F (17°C); precipitation is infrequent.
Fall (September through November)
Fall in Irvine is mild and warm, with daytime highs averaging 78°F (25°C) and nights around 59°F (15°C); precipitation is infrequent.
Winter (December through February)
Winter in Irvine is mild, with daytime highs averaging 66°F (19°C) and nights around 48°F (9°C); rain falls on about 16 days over the three months.
Climate questions, answered
What is the average temperature in Irvine?
Is Irvine hot in summer?
Is Irvine cold in winter?
How many rainy days does Irvine get in a year?
Best time to visit Irvine
The best time to visit Irvine is generally January to June, when temperatures are at their most comfortable before or after the peak heat. Daytime temperatures in that window typically sit near 70°F (21°C).
Pack for Irvine with light layers that can adapt to mild swings through the day. Evenings can feel noticeably cooler than afternoons - August nights average 65°F (18°C).
Irvine temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.