Weather in San Leandro, California
Fog and sun in daily rhythm. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Partly Cloudy—70°50°
- SundayMay 17Overcast—77°49°
- MondayMay 18Overcast—81°57°
- TuesdayMay 19Clear—86°58°
- WednesdayMay 20Overcast—79°60°
- ThursdayMay 21Overcast—78°58°
- FridayMay 22Partly Cloudy—75°58°
- PM 2.5
- 8.9 μg/m³
- PM 10
- 13.7 μg/m³
- NO₂
- 3.7 μg/m³
- Ozone
- 81.0 μg/m³
- UV Index
- 0.3 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 1:10 PM
- Moonset
- 3:46 AM
- In sign
- ♉︎ Taurus
Fog and sun in daily rhythm
San Leandro at a glance
- Today vs. normal: 10°F below the seasonal normal for this latitude
- Last frost: April 2 (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
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
September is San Leandro's warmest month, with a mean temperature near 66°F, and December is its coldest at roughly 52°F. Rainfall peaks in December at 4.7 inches and drops to 0.0 inches in July.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 53° | 4.3″ | 8 |
| February | 55° | 4.3″ | 7 |
| March | 57° | 3.2″ | 7 |
| April | 59° | 1.4″ | 4 |
| May | 61° | 0.8″ | 2 |
| June | 63° | 0.2″ | 1 |
| July | 64° | 0.0″ | 0 |
| August | 65° | 0.1″ | 0 |
| September | 66° | 0.1″ | 0 |
| October | 64° | 1.1″ | 2 |
| November | 58° | 2.4″ | 4 |
| December | 52° | 4.7″ | 8 |
Regional context
San Leandro sits within a hot-summer Mediterranean climate region, a cohort sharing similar temperature ranges, seasonal patterns, and growing conditions with nearby cities.
Similar climates: Los Angeles, CA, San Francisco, CA, San Diego, CA, Riverside, CA, Sacramento, CA.
Naturalist notes
In late spring, valley oaks at this latitude are leafing out fully and their new leaves shift from pale green to leathery dark green by early May.
Barn swallows return to the East Bay in numbers by late April and can be seen skimming low over the San Leandro Creek corridor, hawking insects on warm afternoons.
Frequently asked
- When does it freeze in San Leandro?
- San Leandro's last spring frost typically arrives around mid-April, and the first fall frost around mid-November.
- What is the rainy season in San Leandro?
- December is the wettest month with about 4.7 inches of rain on average; the city receives roughly 23 inches annually.
- What is the warmest month in San Leandro?
- September is typically warmest, averaging about 66°F.
- What is the coldest month in San Leandro?
- December is typically coldest, averaging about 52°F.
- When can I start a vegetable garden in San Leandro?
- Cool-season crops such as peas and lettuce can be sown around the last spring frost in mid-April; warm-season crops like tomatoes and peppers wait until 1–2 weeks after.
- How many rainy days does San Leandro get?
- San Leandro averages about 42 rainy days per year.
- What hardiness zone is San Leandro?
- San Leandro'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
San Leandro, California falls within a hot-summer Mediterranean climate zone. January temperatures hover near 53°F and July averages 64°F, a seasonal swing of 12°F.
The city receives about 23 inches of precipitation over roughly 42 rainy days across the year.
Latitude (37.7°N), proximity to large water bodies, and elevation all set the rhythm of the year. These factors determine what grows, when frost is likely, and the shape of daily weather.