Weather in Rancho Santa Margarita, California
Fog and sun in daily rhythm. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Overcast—71°57°
- SundayMay 17Overcast—71°56°
- MondayMay 18Overcast—77°50°
- TuesdayMay 19Overcast—83°57°
- WednesdayMay 20Overcast—79°60°
- ThursdayMay 21Overcast—78°58°
- FridayMay 22Clear—79°58°
- PM 2.5
- 10.0 μg/m³
- PM 10
- 17.9 μg/m³
- NO₂
- 0.9 μg/m³
- Ozone
- 92.0 μg/m³
- UV Index
- 1.6 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 1:05 PM
- Moonset
- 3:14 AM
- In sign
- ♉︎ Taurus
Fog and sun in daily rhythm
Rancho Santa Margarita at a glance
- Today vs. normal: 15°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 17, 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
Rancho Santa Margarita's warmest month is August (~80°F mean) and its coldest is December (~55°F). Rainfall peaks in February (2.7 inches) and bottoms out in August (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 56° | 2.2″ | 3 |
| February | 56° | 2.7″ | 4 |
| March | 59° | 1.4″ | 2 |
| April | 63° | 0.6″ | 1 |
| May | 68° | 0.2″ | 1 |
| June | 73° | 0.0″ | 0 |
| July | 78° | 0.1″ | 0 |
| August | 80° | 0.0″ | 0 |
| September | 77° | 0.1″ | 0 |
| October | 69° | 0.5″ | 1 |
| November | 61° | 0.6″ | 1 |
| December | 55° | 1.7″ | 3 |
Regional context
Rancho Santa Margarita sits within a hot-summer Mediterranean climate region — a cohort that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Los Angeles, CA, San Francisco, CA, San Diego, CA, Riverside, CA, Sacramento, CA.
Frequently asked
- When does it freeze in Rancho Santa Margarita?
- Rancho Santa Margarita's last spring frost typically falls around mid-March, and the first fall frost arrives around mid-December.
- What is the rainy season in Rancho Santa Margarita?
- February is the wettest month with about 2.7 inches of rain on average; the city receives roughly 10 inches annually.
- What is the warmest month in Rancho Santa Margarita?
- August is typically warmest, averaging about 80°F.
- What is the coldest month in Rancho Santa Margarita?
- December is typically coldest, averaging about 55°F.
- When can I start a vegetable garden in Rancho Santa Margarita?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-March); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Rancho Santa Margarita get?
- Rancho Santa Margarita averages about 17 rainy days per year.
- What hardiness zone is Rancho Santa Margarita?
- Rancho Santa Margarita's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
Rancho Santa Margarita, California sits in a hot-summer Mediterranean climate zone. January means hover near 56°F while July averages 78°F — a 23°F seasonal swing.
Across the year, Rancho Santa Margarita receives about 10 inches of precipitation spread over roughly 17 rainy days.
The rhythm of the year is set by latitude (33.6°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.