Weather in Irvine, California
Fog and sun in daily rhythm. Day 58 of spring. Read this microseason across nine climate regions →
- TodayMay 16Overcast—74°59°
- SundayMay 17Overcast—74°56°
- MondayMay 18Overcast—75°56°
- TuesdayMay 19Overcast—81°61°
- WednesdayMay 20Overcast—77°63°
- ThursdayMay 21Overcast—75°62°
- FridayMay 22Clear—78°62°
- PM 2.5
- 9.9 μg/m³
- PM 10
- 17.4 μg/m³
- NO₂
- 0.8 μg/m³
- Ozone
- 94.0 μg/m³
- UV Index
- 3.0 Moderate
Flowers blooming in late autumn, a sure sign of a bad winter coming.
- Moonrise
- 12:18 PM
- Moonset
- 2:02 AM
- In sign
- ♉︎ Taurus
Fog and sun in daily rhythm
Irvine at a glance
- Today vs. normal: 11°F below the seasonal normal for this latitude
- Last frost: March 9 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Peak growing season
As of May 16, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | — |
| May | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | — | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | — | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | fall brassicas, garlic (overwinter), carrots | — |
| December | — | — |
A year in weather
August brings Irvine's warmest temperatures at around 77°F mean, while December delivers the coldest at approximately 59°F. January sees peak rainfall with 3.2 inches, contrasting sharply with August's bone-dry 0.0 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 60° | 3.2″ | 5 |
| February | 60° | 3.0″ | 5 |
| March | 63° | 1.8″ | 3 |
| April | 65° | 0.7″ | 2 |
| May | 68° | 0.4″ | 1 |
| June | 72° | 0.1″ | 0 |
| July | 76° | 0.1″ | 0 |
| August | 77° | 0.0″ | 0 |
| September | 76° | 0.1″ | 0 |
| October | 71° | 0.6″ | 1 |
| November | 65° | 1.0″ | 2 |
| December | 59° | 2.4″ | 4 |
Regional context
Located within a hot-summer Mediterranean climate region, Irvine shares temperature ranges, seasonal patterns, and growing conditions with other nearby cities in this climate zone.
Similar climates: Los Angeles, CA, San Francisco, CA, San Diego, CA, Riverside, CA, Sacramento, CA.
Naturalist notes
California poppies typically reach peak bloom in late April across Irvine's open spaces.
Allen's hummingbirds begin their northward migration through the area in late February.
Frequently asked
- When does it freeze in Irvine?
- Spring's last frost typically occurs around mid-March in Irvine, while the first fall frost arrives around mid-December.
- What is the rainy season in Irvine?
- January stands as the wettest month, delivering about 3.2 inches of rain on average, while the city receives roughly 14 inches annually.
- What is the warmest month in Irvine?
- August typically brings the warmest weather, averaging about 77°F.
- What is the coldest month in Irvine?
- December typically delivers the coldest temperatures, averaging about 59°F.
- When can I start a vegetable garden in Irvine?
- Cool-season crops like peas and lettuce can be planted around the last spring frost in mid-March, while warm-season crops such as tomatoes and peppers should wait until 1–2 weeks after.
- How many rainy days does Irvine get?
- Irvine experiences about 23 rainy days per year on average.
- What hardiness zone is Irvine?
- Irvine's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool can provide the current zone designation using the city ZIP code.
Climate
Irvine, California experiences a hot-summer Mediterranean climate. January temperatures hover near 60°F while July averages 76°F, creating a 16°F seasonal swing.
Annual precipitation totals about 14 inches, falling across roughly 23 rainy days throughout the year.
Weather patterns here follow the city's latitude at 33.7°N, along with its proximity to large water bodies and elevation. These factors determine what grows in the area, when frost occurs, and daily weather conditions.