USDA Hardiness Zone 10a
Frost Dates for 90041 — Los Angeles, California
NOAA 1991–2020 normals from Pasadena, CA (864 ft), 4 miles east.
Updated
Frost is not a yearly event in Los Angeles: a night at or below 32°F came in 13% of the winters of 1991–2020 at Pasadena, CA, and a 36°F night, cold enough for frost on exposed leaves, in 75%. There is no reliable "last frost date" here; most years have none.
- Winters with a freeze
- 13%
- Winters with 36°F
- 75%
- Coldest month low
- 45°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 20 observed
NOAA normal
Frost risk by date in Los Angeles
At Pasadena, CA, 4 miles east of Los Angeles, 13% of the winters of 1991–2020 had at least one night at or below 32°F, 0% reached 28°F. Nights of 36°F, enough for frost on exposed leaves, are more common (75% of winters) and, when they come, fall between about December 28 and January 17. January is the month most likely to bring one: a 8% 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°F75% of yrs | Dec 18 | Dec 31 | Jan 5 | Jan 11 | Jan 17 | Jan 27 | Feb 6 | Feb 17 | Feb 27 |
| 32°F13% of yrs | too rare for a date | ||||||||
| 28°F0% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F75% of yrs | Dec 5 | Dec 12 | Dec 18 | Dec 22 | Dec 28 | Jan 1 | Jan 7 | Jan 20 | Feb 7 |
| 32°F13% of yrs | too rare for a date | ||||||||
| 28°F0% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Pasadena, 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 90041 →Compare Los Angeles with another place →
Weather by month in Los Angeles
August is the warmest month at Pasadena, CA, averaging 91°F by day and 63°F at night; December is the coldest at 67°F and 45°F. Every month stays under a 10% chance of a 32°F night; January is the likeliest at 8%.
Warmth for growing adds up to 5,867 growing degree days a year (base 50°F), more than at 87% of the 283 California stations. 39% of them (2,291) have built up by the end of June, and August adds the most, 845. Precipitation totals 20.0 inches a year, most in February (5.2") 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 | 68 | 46 | 4.5 | 8% | 0 | 219 |
| Feb | 69 | 46 | 5.2 | 2% | 0 | 221 |
| Mar | 73 | 48 | 3.0 | 0% | 0 | 328 |
| Apr | 76 | 51 | 1.1 | 0% | 0 | 402 |
| May | 78 | 54 | 0.5 | 0% | 0 | 499 |
| Jun | 84 | 58 | 0.2 | 0% | 0 | 623 |
| Jul | 89 | 62 | 0.1 | 0% | 0 | 792 |
| Aug | 91 | 63 | 0.0 | 0% | 0 | 845 |
| Sep | 90 | 62 | 0.2 | 0% | 0 | 773 |
| Oct | 83 | 56 | 0.8 | 0% | 0 | 609 |
| Nov | 75 | 50 | 1.1 | 0% | 0 | 365 |
| Dec | 67 | 45 | 3.3 | 3% | 0 | 192 |
Monthly normals 1991–2020 at Pasadena, CA (864 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, Los Angeles Dwtn Usc Campus, CA, 6 miles south of Los Angeles and 634 feet lower, has a 32°F night in 0% of winters against 13% here, and a coolest-month low 3°F warmer (48°F).
When it snows in Los Angeles, California
Measurable snow is rare here: only 0 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Pasadena, CA, 3.7 miles away, so there is no typical first-snow date to plan around.
Where these figures come from
ZIP 90041 is 4 miles from Pasadena, CA, which stands at 864 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 16 other ZIP codes share the station; its figures are presented in full for 90042 (Los Angeles). The 2023 USDA Plant Hardiness Zone Map lists ZIP 90041 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.