USDA Hardiness Zone 9a
Frost Dates for 95341 — Merced, California
NOAA 1991–2020 normals from Merced Municipal Airport, CA (152 ft), 10 miles northeast.
Updated
In Merced, the last spring frost (32°F) is around February 26 in half of years and has passed by April 1 in nine years out of ten. The first fall frost comes around November 25, as early as November 9 one year in ten, leaving a typical freeze-free season of 273 days (NOAA, Merced Municipal Airport, CA).
- Last spring frost
- February 26
- First fall frost
- November 25
- Growing season
- 273 days
- Hardiness zone
- 9a
50% probability
50% probability
freeze-free, 50%
20 to 25°F (-6.7 to -3.9°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 Merced
Half of springs at Merced Municipal Airport, CA see their last 32°F night by February 26; only one in ten is past it by January 20, and one in ten still has one after April 1. Planting tender crops after March 8 leaves a 30% risk of a frost on them, after March 17 20%, and after April 1 10%. The 34 days between the even-odds date and the one-in-ten date is wider than at 65% 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 November 25 in half of years, as early as November 9 one year in ten, and holds off past December 16 one year in ten. A hard freeze of 28°F follows 15 days later, around December 10; in spring the one-in-ten date for 28°F is February 24, 36 days before the 32°F one. The freeze-free season lasts 273 days in a typical year, shorter than at 53% of the 219 California stations; it reaches 314 days one year in ten and falls short of 236 one year in ten. On average 28 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 April 2, and return around November 11. A 24°F night is unusual: 44% of winters had one.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 5 | Mar 15 | Mar 23 | Mar 29 | Apr 2 | Apr 6 | Apr 9 | Apr 14 | Apr 19 |
| 32°F | Jan 20 | Feb 3 | Feb 14 | Feb 20 | Feb 26 | Mar 2 | Mar 8 | Mar 17 | Apr 1 |
| 28°F90% of yrs | Dec 21 | Dec 31 | Jan 5 | Jan 14 | Jan 22 | Jan 30 | Feb 6 | Feb 13 | Feb 24 |
| 24°F44% of yrs | too rare for a date | ||||||||
| 20°F9% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 26 | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 26 |
| 32°F | Nov 9 | Nov 15 | Nov 19 | Nov 22 | Nov 25 | Nov 28 | Dec 1 | Dec 6 | Dec 16 |
| 28°F90% of yrs | Nov 23 | Nov 29 | Dec 2 | Dec 6 | Dec 10 | Dec 16 | Dec 24 | Jan 1 | Jan 12 |
| 24°F44% of yrs | too rare for a date | ||||||||
| 20°F9% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Merced 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 95341 →Compare Merced with another place →
Weather by month in Merced
July is the warmest month at Merced Municipal Airport, CA, averaging 96°F by day and 62°F at night; December is the coldest at 56°F and 36°F. From May to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 73% of years and March still brings one in 37% of years and April still brings one in 10% of years.
Warmth for growing adds up to 4,882 growing degree days a year (base 50°F), more than at 60% of the 283 California stations. 37% of them (1,817) have built up by the end of June, and July adds the most, 899. Precipitation totals 11.8 inches a year, most in January (2.4") and least in July (0.0"); May to September bring 7% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 56 | 37 | 2.4 | 89% | 8 | 19 |
| Feb | 62 | 39 | 2.2 | 73% | 4 | 64 |
| Mar | 68 | 42 | 1.8 | 37% | 1 | 176 |
| Apr | 74 | 45 | 1.1 | 10% | <1 | 294 |
| May | 83 | 52 | 0.6 | 0% | 0 | 539 |
| Jun | 91 | 58 | 0.1 | 0% | 0 | 725 |
| Jul | 96 | 62 | 0.0 | 0% | 0 | 899 |
| Aug | 95 | 61 | 0.0 | 0% | 0 | 863 |
| Sep | 91 | 57 | 0.1 | 0% | 0 | 705 |
| Oct | 80 | 49 | 0.6 | 2% | 0 | 444 |
| Nov | 66 | 41 | 1.0 | 67% | 3 | 133 |
| Dec | 56 | 36 | 1.9 | 89% | 11 | 21 |
Monthly normals 1991–2020 at Merced Municipal Airport, CA (152 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, Merced, CA, 10 miles northeast of Merced, has a last frost 5 days later (March 3), a first frost 1 day earlier (November 24), a season 10 days shorter.
When it snows in Merced, California
Measurable snow is rare here: only 0 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Merced, CA, 10.2 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 95341
| When | What to do |
|---|---|
| December 18 – January 1 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| January 1 – January 15 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| January 29 – February 12 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| February 26 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by September 2 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 11 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 25 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 95341 is 10 miles from Merced Municipal Airport, CA, which stands at 152 feet, 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 95340 (Merced). The 2023 USDA Plant Hardiness Zone Map lists ZIP 95341 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°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.