USDA Hardiness Zone 10a
Frost Dates for 92249 — Heber, California
NOAA 1991–2020 normals from El Centro 2 SSW, CA, 4 miles northwest.
Updated
A freeze (32°F) reaches Heber in 54% of winters. When it does, the first fall frost comes around December 27 and the last spring frost around January 3; after February 4 the chance of another is under 5%.
- Last spring frost
- January 3
- First fall frost
- December 27
- Winters with a freeze
- 54%
- Hardiness zone
- 10a
50%, in freezing years
50%, in freezing years
32°F or below, 1991–2020
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 24 observed
NOAA normal
Frost risk by date in Heber
In the 54% of winters that bring a 32°F night, half of springs at El Centro 2 SSW, CA see their last 32°F night by January 3; only one in ten is past it by December 15, and one in ten still has one after February 4. Counting the winters with no freeze at all, the risk of a 32°F night after February 4 is under 5% and after January 3 27%. The 32 days between the even-odds date and the one-in-ten date is wider than at 55% 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 27 in half of years, as early as December 9 one year in ten, and holds off past January 26 one year in ten. A hard freeze of 28°F is less common: it came in 14% of winters. The freeze-free season lasts 363 days in a typical year, longer than at 100% of the 219 California stations; it reaches 365 days one year in ten and falls short of 332 one year in ten. On average 1 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 19 days longer, to about January 22, and return around December 17. No night reached 24°F in 1991–2020.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F94% of yrs | Dec 27 | Jan 3 | Jan 9 | Jan 15 | Jan 22 | Jan 29 | Feb 4 | Feb 12 | Feb 22 |
| 32°F54% of yrs | Dec 15 | Dec 23 | Dec 28 | Dec 31 | Jan 3 | Jan 8 | Jan 15 | Jan 25 | Feb 4 |
| 28°F14% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F94% of yrs | Nov 30 | Dec 6 | Dec 10 | Dec 14 | Dec 17 | Dec 20 | Dec 24 | Dec 30 | Jan 9 |
| 32°F54% of yrs | Dec 9 | Dec 16 | Dec 21 | Dec 24 | Dec 27 | Dec 31 | Jan 3 | Jan 12 | Jan 26 |
| 28°F14% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at El Centro 2 SSW, 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 92249 →Compare Heber with another place →
Weather by month in Heber
August is the warmest month at El Centro 2 SSW, CA, averaging 107°F by day and 79°F at night; December is the coldest at 70°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 8,902 growing degree days a year (base 50°F), more than at 98% of the 283 California stations. 41% of them (3,649) have built up by the end of June, and August adds the most, 1,333. Precipitation totals 2.6 inches a year, most in January (0.4") and least in May (0.0"); May to September bring 23% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 71 | 43 | 0.4 | 26% | 1 | 228 |
| Feb | 74 | 47 | 0.4 | 7% | <1 | 292 |
| Mar | 80 | 52 | 0.3 | 0% | 0 | 494 |
| Apr | 86 | 57 | 0.1 | 0% | 0 | 647 |
| May | 94 | 63 | 0.0 | 0% | 0 | 885 |
| Jun | 103 | 71 | 0.0 | 0% | 0 | 1104 |
| Jul | 107 | 78 | 0.1 | 0% | 0 | 1316 |
| Aug | 107 | 79 | 0.2 | 0% | 0 | 1333 |
| Sep | 102 | 73 | 0.3 | 0% | 0 | 1128 |
| Oct | 92 | 62 | 0.2 | 0% | 0 | 828 |
| Nov | 79 | 51 | 0.2 | 1% | 0 | 449 |
| Dec | 70 | 43 | 0.4 | 33% | <1 | 199 |
Monthly normals 1991–2020 at El Centro 2 SSW, CA, 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, Imperial, CA, 9 miles north of Heber, has a last frost 1 day later (January 4), a first frost 1 day earlier (December 26), a season 3 days shorter.
When it snows in Heber, California
Measurable snow is rare here: only 0 of 24 winters from 1991 to 2020 recorded 0.1 inch or more at El Centro 2 SSW, CA, 4 miles away, so there is no typical first-snow date to plan around.
Where these figures come from
ZIP 92249 is 4 miles from El Centro 2 SSW, CA, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 92243 (El Centro). The 2023 USDA Plant Hardiness Zone Map lists ZIP 92249 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.