Weather in Bethel Island, California
Fog and sun in daily rhythm. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Mostly Clear—80°57°
- SundayMay 17Overcast—75°54°
- MondayMay 18Clear—86°57°
- TuesdayMay 19Clear—92°55°
- WednesdayMay 20Overcast—97°56°
- ThursdayMay 21Overcast—95°58°
- FridayMay 22Overcast—92°55°
- PM 2.5
- 4.6 μg/m³
- PM 10
- 27.9 μg/m³
- NO₂
- 1.1 μg/m³
- Ozone
- 109.0 μg/m³
- UV Index
- 2.2 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 1:07 PM
- Moonset
- 3:45 AM
- In sign
- ♉︎ Taurus
Fog and sun in daily rhythm
Bethel Island at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: April 4 (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
Bethel Island's warmest month is July (~76°F mean) and its coldest is January (~48°F). Rainfall peaks in January (2.7 inches) and bottoms out in July (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 48° | 2.7″ | 6 |
| February | 52° | 2.4″ | 6 |
| March | 57° | 1.9″ | 5 |
| April | 61° | 0.9″ | 2 |
| May | 67° | 0.4″ | 1 |
| June | 73° | 0.1″ | 0 |
| July | 76° | 0.0″ | 0 |
| August | 75° | 0.0″ | 0 |
| September | 73° | 0.1″ | 0 |
| October | 66° | 0.4″ | 1 |
| November | 55° | 1.2″ | 3 |
| December | 48° | 2.5″ | 6 |
Frequently asked
- When does it freeze in Bethel Island?
- Bethel Island's last spring frost typically falls around mid-April, and the first fall frost arrives around mid-November.
- What is the rainy season in Bethel Island?
- January is the wettest month with about 2.7 inches of rain on average; the city receives roughly 13 inches annually.
- What is the warmest month in Bethel Island?
- July is typically warmest, averaging about 76°F.
- What is the coldest month in Bethel Island?
- January is typically coldest, averaging about 48°F.
- When can I start a vegetable garden in Bethel Island?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-April); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Bethel Island get?
- Bethel Island averages about 30 rainy days per year.
- What hardiness zone is Bethel Island?
- Bethel Island'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
Bethel Island, California sits in a hot-summer Mediterranean climate zone. January means hover near 48°F while July averages 76°F — a 28°F seasonal swing.
Across the year, Bethel Island receives about 13 inches of precipitation spread over roughly 30 rainy days.
The rhythm of the year is set by latitude (38.0°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.