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USDA Hardiness Zone 9a

Frost Dates for 95648 — Lincoln, California

NOAA 1991–2020 normals from Auburn, CA (1,292 ft), 12 miles east.

Updated

In Lincoln, the last spring frost (32°F) is around February 25 in half of years and has passed by April 7 in nine years out of ten. The first fall frost comes around December 5, as early as November 15 one year in ten, leaving a typical freeze-free season of 286 days (NOAA, Auburn, CA).

Last spring frost
February 25

50% probability

First fall frost
December 5

50% probability

Growing season
286 days

freeze-free, 50%

Hardiness zone
9a

20 to 25°F (-6.7 to -3.9°C) coldest night

First snow
Rare

median, 1991–2020

Last snow
Rare

median, 1991–2020

Winters with snow
25%

5 of 20 observed

Snow per year
—

NOAA normal

Frost risk by date in Lincoln

Half of springs at Auburn, CA see their last 32°F night by February 25; only one in ten is past it by January 15, and one in ten still has one after April 7. Planting tender crops after March 14 leaves a 30% risk of a frost on them, after March 28 20%, and after April 7 10%. The 41 days between the even-odds date and the one-in-ten date is wider than at 89% 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 5 in half of years, as early as November 15 one year in ten, and holds off past December 31 one year in ten. A hard freeze of 28°F follows 17 days later, around December 22; in spring the one-in-ten date for 28°F is February 25, 41 days before the 32°F one. The freeze-free season lasts 286 days in a typical year, longer than at 57% of the 219 California stations; it reaches 330 days one year in ten and falls short of 236 one year in ten. On average 20 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 39 days longer, to about April 5, and return around November 19. A 24°F night is unusual: 30% of winters had one.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FMar 2Mar 14Mar 23Mar 31Apr 5Apr 10Apr 15Apr 20Apr 30
32°F99% of yrsJan 15Jan 27Feb 5Feb 16Feb 25Mar 3Mar 14Mar 28Apr 7
28°F81% of yrsDec 19Dec 28Jan 2Jan 7Jan 13Jan 20Jan 31Feb 12Feb 25
24°F30% of yrstoo rare for a date
20°F5% of yrstoo rare for a date
16°F2% of yrstoo rare for a date
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FOct 30Nov 6Nov 12Nov 16Nov 19Nov 23Nov 27Dec 1Dec 7
32°F99% of yrsNov 15Nov 22Nov 28Dec 1Dec 5Dec 9Dec 13Dec 19Dec 31
28°F81% of yrsDec 1Dec 7Dec 12Dec 16Dec 22Dec 27Jan 1Jan 8Jan 22
24°F30% of yrstoo rare for a date
20°F5% of yrstoo rare for a date
16°F2% of yrstoo rare for a date

Freeze probabilities 1991–2020 at Auburn, 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 95648 →Compare Lincoln with another place →

Weather by month in Lincoln

July is the warmest month at Auburn, CA, averaging 93°F by day and 63°F at night; December is the coldest at 56°F and 37°F. From May to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 55% of years and March still brings one in 34% of years and April still brings one in 16% of years.

Warmth for growing adds up to 4,541 growing degree days a year (base 50°F), fewer than at 52% of the 283 California stations. 34% of them (1,522) have built up by the end of June, and July adds the most, 870. Precipitation totals 36.1 inches a year, most in January (7.0") and least in July (0.0"); May to September bring 7% of it.

Monthly normals 1991–2020 at Auburn, CA
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan56387.087%629
Feb59406.555%362
Mar63426.134%1130
Apr68452.816%1211
May77521.70%0442
Jun86580.40%0648
Jul93630.00%0870
Aug92630.10%0849
Sep87600.20%0695
Oct77521.42%<1443
Nov64433.134%1140
Dec56376.885%823

Monthly normals 1991–2020 at Auburn, CA (1,292 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, Marysville Yuba Co Airport, CA, 20 miles northwest of Lincoln and 1,230 feet lower, has a last frost 14 days earlier (February 11), a first frost 5 days earlier (November 30), a season 3 days longer.

Frost dates for 95961 (Olivehurst) →

When it snows in Lincoln, California

Measurable snow is rare here: only 5 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Auburn, CA, 11.5 miles away, so there is no typical first-snow date to plan around.

Planting calendar for 95648

What to do and when, from the 50% frost dates for Lincoln, California
WhenWhat to do
December 17 – December 31Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
December 31 – January 14Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
January 28 – February 11Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
February 25 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by September 12Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by November 21Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
December 5 onwardPlant 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 95648 is 12 miles from Auburn, CA, which stands at 1,292 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 9 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 95648 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.

ZIP codes measured at the same station

Other zone 9a places in California