USDA Hardiness Zone 10a
Frost Dates for 92057 — Oceanside, California
NOAA 1991–2020 normals from Oceanside Municipal Airport, CA (28 ft), 3 miles southwest.
Updated
In Oceanside, the last spring frost (32°F) is around January 23 in half of years and has passed by February 22 in nine years out of ten. The first fall frost comes around December 11, as early as November 21 one year in ten, leaving a typical freeze-free season of 325 days (NOAA, Oceanside Municipal Airport, CA).
- Last spring frost
- January 23
- First fall frost
- December 11
- Growing season
- 325 days
- Hardiness zone
- 10a
50% probability
50% probability
freeze-free, 50%
30 to 35°F (-1.1 to 1.7°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 5%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
1 of 19 observed
NOAA normal
Frost risk by date in Oceanside
Half of springs at Oceanside Municipal Airport, CA see their last 32°F night by January 23; only one in ten is past it by December 22, and one in ten still has one after February 22. Planting tender crops after February 4 leaves a 30% risk of a frost on them, after February 12 20%, and after February 22 10%. The 30 days between the even-odds date and the one-in-ten date is narrower than at 48% of the 220 California stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.
In fall the first 32°F night comes by December 11 in half of years, as early as November 21 one year in ten, and holds off past January 15 one year in ten. A hard freeze of 28°F is less common: it came in 41% of winters. The freeze-free season lasts 325 days in a typical year, longer than at 78% of the 219 California stations; it reaches 360 days one year in ten and falls short of 287 one year in ten. On average 8 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 35 days longer, to about February 27, and return around November 24. A 24°F night is unusual: 3% of winters had one.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jan 29 | Feb 7 | Feb 15 | Feb 21 | Feb 27 | Mar 3 | Mar 11 | Mar 22 | Apr 6 |
| 32°F91% of yrs | Dec 22 | Dec 31 | Jan 6 | Jan 14 | Jan 23 | Jan 31 | Feb 4 | Feb 12 | Feb 22 |
| 28°F41% of yrs | too rare for a date | ||||||||
| 24°F3% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 7 | Nov 13 | Nov 17 | Nov 20 | Nov 24 | Nov 27 | Dec 1 | Dec 5 | Dec 12 |
| 32°F91% of yrs | Nov 21 | Nov 27 | Dec 1 | Dec 6 | Dec 11 | Dec 15 | Dec 20 | Dec 29 | Jan 15 |
| 28°F41% of yrs | too rare for a date | ||||||||
| 24°F3% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Oceanside Municipal Airport, 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 92057 →Compare Oceanside with another place →
Weather by month in Oceanside
August is the warmest month at Oceanside Municipal Airport, CA, averaging 78°F by day and 62°F at night; December is the coldest at 66°F and 40°F. From March to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 33% of years.
Warmth for growing adds up to 4,072 growing degree days a year (base 50°F), fewer than at 58% of the 283 California stations. 38% of them (1,534) have built up by the end of June, and August adds the most, 626. Precipitation totals 11.9 inches a year, most in February (2.9") and least in August (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 | 67 | 41 | 2.4 | 58% | 3 | 127 |
| Feb | 66 | 42 | 2.9 | 33% | 1 | 125 |
| Mar | 66 | 46 | 1.7 | 4% | <1 | 196 |
| Apr | 69 | 48 | 0.9 | 0% | 0 | 248 |
| May | 70 | 54 | 0.3 | 0% | 0 | 375 |
| Jun | 73 | 58 | 0.1 | 0% | 0 | 464 |
| Jul | 77 | 62 | 0.1 | 0% | 0 | 598 |
| Aug | 78 | 62 | 0.0 | 0% | 0 | 626 |
| Sep | 78 | 59 | 0.1 | 0% | 0 | 555 |
| Oct | 75 | 53 | 0.6 | 0% | 0 | 428 |
| Nov | 71 | 44 | 0.8 | 25% | <1 | 223 |
| Dec | 66 | 40 | 2.0 | 67% | 4 | 108 |
Monthly normals 1991–2020 at Oceanside Municipal Airport, CA (28 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, Vista, CA, 4 miles east of Oceanside and 402 feet higher, has a 32°F night in 35% of winters against 91% here, and a coolest-month low 5°F warmer (45°F).
When it snows in Oceanside, California
Measurable snow is rare here: only 1 of 19 winters from 1991 to 2020 recorded 0.1 inch or more at Vista, CA, 3.9 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 92057
| When | What to do |
|---|---|
| November 14 – November 28 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| November 28 – December 12 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| December 26 – January 9 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| January 23 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by September 18 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 27 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| December 11 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 92057 is 3 miles from Oceanside Municipal Airport, CA, which stands at 28 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 92057 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.