USDA Hardiness Zone 10a
Frost Dates for 94618 — Oakland, California
NOAA 1991–2020 normals from Berkeley, CA (310 ft), 2 miles northwest.
Updated
Frost is not a yearly event in Oakland: a night at or below 32°F came in 27% of the winters of 1991–2020 at Berkeley, CA, and a 36°F night, cold enough for frost on exposed leaves, in 93%. There is no reliable "last frost date" here; most years have none.
- Winters with a freeze
- 27%
- Winters with 36°F
- 93%
- Coldest month low
- 43°F
- Hardiness zone
- 10a
32°F or below, 1991–2020
frost possible on leaves
average, December
30 to 35°F (-1.1 to 1.7°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 0%
- Snow per year
- 0"
median, 1991–2020
median, 1991–2020
0 of 17 observed
NOAA normal
Frost risk by date in Oakland
At Berkeley, CA, 2 miles northwest of Oakland, 27% of the winters of 1991–2020 had at least one night at or below 32°F, 1% reached 28°F. Nights of 36°F, enough for frost on exposed leaves, are more common (93% of winters) and, when they come, fall between about December 19 and February 5. December is the month most likely to bring one: a 13% chance in a given year. 62 of the 283 other California stations behind this site's ZIP pages freeze in fewer than half of winters too.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F93% of yrs | Dec 29 | Jan 7 | Jan 16 | Jan 27 | Feb 5 | Feb 15 | Feb 25 | Mar 5 | Mar 20 |
| 32°F27% of yrs | too rare for a date | ||||||||
| 28°F1% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F93% of yrs | Nov 27 | Dec 4 | Dec 9 | Dec 14 | Dec 19 | Dec 25 | Dec 31 | Jan 7 | Jan 26 |
| 32°F27% of yrs | too rare for a date | ||||||||
| 28°F1% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Berkeley, CA, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 94618 →Compare Oakland with another place →
Weather by month in Oakland
September is the warmest month at Berkeley, CA, averaging 76°F by day and 54°F at night; December is the coldest at 59°F and 43°F. From February to November the chance of a 32°F night stays under 10% each month.
Warmth for growing adds up to 3,213 growing degree days a year (base 50°F), fewer than at 79% of the 283 California stations. 39% of them (1,250) have built up by the end of June, and September adds the most, 449. Precipitation totals 26.0 inches a year, most in December (5.3") and least in July (0.0"); May to September bring 5% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 59 | 43 | 4.8 | 13% | <1 | 71 |
| Feb | 62 | 45 | 5.1 | 2% | 0 | 106 |
| Mar | 65 | 46 | 3.8 | 1% | 0 | 172 |
| Apr | 67 | 47 | 1.8 | 0% | 0 | 213 |
| May | 70 | 49 | 0.8 | 0% | 0 | 301 |
| Jun | 74 | 52 | 0.3 | 0% | 0 | 387 |
| Jul | 74 | 53 | 0.0 | 0% | 0 | 425 |
| Aug | 75 | 54 | 0.1 | 0% | 0 | 448 |
| Sep | 76 | 54 | 0.1 | 0% | 0 | 449 |
| Oct | 73 | 52 | 1.2 | 0% | 0 | 388 |
| Nov | 65 | 47 | 2.7 | 0% | 0 | 189 |
| Dec | 59 | 43 | 5.3 | 13% | <1 | 66 |
Monthly normals 1991–2020 at Berkeley, CA (310 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Oakland Museum, CA, 3 miles south of Oakland and 280 feet lower, has a 32°F night in 3% of winters against 27% here, and a coolest-month low 2°F warmer (45°F).
When it snows in Oakland, California
Measurable snow is rare here: only 0 of 17 winters from 1991 to 2020 recorded 0.1 inch or more at Berkeley, CA, 2.3 miles away, so there is no typical first-snow date to plan around.
Where these figures come from
ZIP 94618 is 2 miles from Berkeley, CA, which stands at 310 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 13 other ZIP codes share the station; its figures are presented in full for 94530 (El Cerrito). The 2023 USDA Plant Hardiness Zone Map lists ZIP 94618 in zone 10a, the band where the coldest night of the year averaged 30 to 35°F (-1.1 to 1.7°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across California →
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.