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USDA Hardiness Zone 9b

Frost Dates for 92065 — Ramona, California

NOAA 1991–2020 normals from Ramona Fire Dept, CA (1,470 ft), 4 miles southwest.

Updated

In Ramona, the last spring frost (32°F) is around March 4 in half of years and has passed by April 10 in nine years out of ten. The first fall frost comes around December 4, as early as November 17 one year in ten, leaving a typical freeze-free season of 270 days (NOAA, Ramona Fire Dept, CA).

Last spring frost
March 4

50% probability

First fall frost
December 4

50% probability

Growing season
270 days

freeze-free, 50%

Hardiness zone
9b

25 to 30°F (-3.9 to -1.1°C) coldest night

First snow
Rare

median, 1991–2020

Last snow
Rare

median, 1991–2020

Winters with snow
0%

0 of 18 observed

Snow per year
0"

NOAA normal

Frost risk by date in Ramona

Half of springs at Ramona Fire Dept, CA see their last 32°F night by March 4; only one in ten is past it by January 29, and one in ten still has one after April 10. Planting tender crops after March 23 leaves a 30% risk of a frost on them, after March 31 20%, and after April 10 10%. The 37 days between the even-odds date and the one-in-ten date is wider than at 79% 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 4 in half of years, as early as November 17 one year in ten, and holds off past December 18 one year in ten. A hard freeze of 28°F follows 15 days later, around December 19; in spring the one-in-ten date for 28°F is March 1, 40 days before the 32°F one. The freeze-free season lasts 270 days in a typical year, shorter than at 58% of the 219 California stations; it reaches 308 days one year in ten and falls short of 234 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 37 days longer, to about April 10, and return around November 19. A 24°F night is unusual: 38% 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 17Mar 30Apr 3Apr 6Apr 10Apr 13Apr 17Apr 21Apr 28
32°FJan 29Feb 13Feb 21Feb 27Mar 4Mar 11Mar 23Mar 31Apr 10
28°F92% of yrsDec 23Dec 31Jan 11Jan 20Jan 31Feb 8Feb 15Feb 23Mar 1
24°F38% of yrstoo rare for a date
20°F3% 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 26Nov 3Nov 9Nov 14Nov 19Nov 22Nov 26Dec 1Dec 4
32°FNov 17Nov 25Nov 30Dec 2Dec 4Dec 7Dec 11Dec 14Dec 18
28°F92% of yrsDec 1Dec 8Dec 12Dec 16Dec 19Dec 23Dec 27Jan 2Jan 16
24°F38% of yrstoo rare for a date
20°F3% of yrstoo rare for a date

Freeze probabilities 1991–2020 at Ramona Fire Dept, 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 92065 →Compare Ramona with another place →

Weather by month in Ramona

August is the warmest month at Ramona Fire Dept, CA, averaging 92°F by day and 59°F at night; December is the coldest at 67°F and 37°F. A freezing night is all but certain in every month from December to January (a 90% chance or more). From May to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 77% of years and March still brings one in 45% of years and April still brings one in 20% of years.

Warmth for growing adds up to 4,659 growing degree days a year (base 50°F), more than at 52% of the 283 California stations. 34% of them (1,602) have built up by the end of June, and August adds the most, 798. Precipitation totals 14.5 inches a year, most in February (3.5") and least in June (0.1"); May to September bring 6% of it.

Monthly normals 1991–2020 at Ramona Fire Dept, CA
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan68383.191%7114
Feb68393.577%5113
Mar69412.745%2172
Apr73431.120%1253
May77490.40%0402
Jun85520.10%0549
Jul90570.10%0735
Aug92590.10%0798
Sep90550.20%0679
Oct82490.52%<1481
Nov74431.231%3269
Dec67371.598%1096

Monthly normals 1991–2020 at Ramona Fire Dept, CA (1,470 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, Rancho Bernardo, CA, 13 miles west of Ramona and 780 feet lower, has a 32°F night in 21% of winters against 100% here.

Frost dates for 92129 (San Diego) →

When it snows in Ramona, California

Measurable snow is rare here: only 0 of 18 winters from 1991 to 2020 recorded 0.1 inch or more at Ramona Fire Dept, CA, 3.7 miles away, so there is no typical first-snow date to plan around.

Planting calendar for 92065

What to do and when, from the 50% frost dates for Ramona, California
WhenWhat to do
December 24 – January 7Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
January 7 – January 21Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
February 4 – February 18Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
March 4 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by September 11Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by November 20Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
December 4 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 92065 is 4 miles from Ramona Fire Dept, CA, which stands at 1,470 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 92058 (Oceanside). The 2023 USDA Plant Hardiness Zone Map lists ZIP 92065 in zone 9b, the band where the coldest night of the year averaged 25 to 30°F (-3.9 to -1.1°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 9b places in California