USDA Hardiness Zone 9b
Frost Dates for 96001 — Redding, California
NOAA 1991–2020 normals from Whiskeytown Rsvr, CA (1,295 ft), 7 miles northwest.
Updated
In Redding, the last spring frost (32°F) is around February 13 in half of years and has passed by March 25 in nine years out of ten. The first fall frost comes around December 13, as early as November 20 one year in ten, leaving a typical freeze-free season of 304 days (NOAA, Whiskeytown Rsvr, CA).
- Last spring frost
- February 13
- First fall frost
- December 13
- Growing season
- 304 days
- Hardiness zone
- 9b
50% probability
50% probability
freeze-free, 50%
25 to 30°F (-3.9 to -1.1°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 18%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
5 of 28 observed
NOAA normal
Frost risk by date in Redding
Half of springs at Whiskeytown Rsvr, CA see their last 32°F night by February 13; only one in ten is past it by December 30, and one in ten still has one after March 25. Planting tender crops after February 28 leaves a 30% risk of a frost on them, after March 8 20%, and after March 25 10%. The 40 days between the even-odds date and the one-in-ten date is wider than at 85% 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 13 in half of years, as early as November 20 one year in ten, and holds off past January 19 one year in ten. A hard freeze of 28°F is less common: it came in 49% of winters. The freeze-free season lasts 304 days in a typical year, longer than at 66% of the 219 California stations; it reaches 349 days one year in ten and falls short of 259 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 42 days longer, to about March 27, and return around November 26. A 24°F night is unusual: 8% of winters had one.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Feb 18 | Mar 1 | Mar 11 | Mar 20 | Mar 27 | Apr 1 | Apr 6 | Apr 12 | Apr 20 |
| 32°F96% of yrs | Dec 30 | Jan 13 | Jan 26 | Feb 5 | Feb 13 | Feb 21 | Feb 28 | Mar 8 | Mar 25 |
| 28°F49% of yrs | too rare for a date | ||||||||
| 24°F8% of yrs | too rare for a date | ||||||||
| 20°F2% of yrs | too rare for a date | ||||||||
| 16°F0% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 6 | Nov 13 | Nov 17 | Nov 21 | Nov 26 | Nov 30 | Dec 2 | Dec 7 | Dec 15 |
| 32°F96% of yrs | Nov 20 | Nov 28 | Dec 3 | Dec 8 | Dec 13 | Dec 18 | Dec 25 | Jan 1 | Jan 19 |
| 28°F49% of yrs | too rare for a date | ||||||||
| 24°F8% of yrs | too rare for a date | ||||||||
| 20°F2% of yrs | too rare for a date | ||||||||
| 16°F0% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Whiskeytown Rsvr, 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 96001 →Compare Redding with another place →
Weather by month in Redding
July is the warmest month at Whiskeytown Rsvr, CA, averaging 99°F by day and 67°F at night; December is the coldest at 54°F and 39°F. From April to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 49% of years and March still brings one in 21% of years.
Warmth for growing adds up to 5,188 growing degree days a year (base 50°F), more than at 70% of the 283 California stations. 35% of them (1,799) have built up by the end of June, and July adds the most, 1,010. Precipitation totals 63.0 inches a year, most in February (11.6") and least in August (0.1"); May to September bring 8% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 54 | 39 | 10.7 | 64% | 6 | 31 |
| Feb | 58 | 41 | 11.6 | 49% | 4 | 64 |
| Mar | 63 | 43 | 9.9 | 21% | 1 | 148 |
| Apr | 70 | 47 | 5.0 | 6% | <1 | 267 |
| May | 79 | 55 | 3.1 | 0% | 0 | 531 |
| Jun | 89 | 62 | 1.3 | 0% | 0 | 758 |
| Jul | 99 | 67 | 0.2 | 0% | 0 | 1010 |
| Aug | 98 | 65 | 0.1 | 0% | 0 | 972 |
| Sep | 92 | 61 | 0.5 | 0% | 0 | 790 |
| Oct | 78 | 52 | 2.8 | 0% | 0 | 467 |
| Nov | 62 | 44 | 6.3 | 23% | 2 | 127 |
| Dec | 54 | 39 | 11.5 | 70% | 7 | 22 |
Monthly normals 1991–2020 at Whiskeytown Rsvr, CA (1,295 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, Redding Municipal Airport, CA, 7 miles southeast of Redding and 798 feet lower, has a last frost 18 days later (March 3), a first frost 22 days earlier (November 21), a season 43 days shorter.
When it snows in Redding, California
Measurable snow is rare here: only 5 of 28 winters from 1991 to 2020 recorded 0.1 inch or more at Whiskeytown Rsvr, CA, 6.6 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 96001
| When | What to do |
|---|---|
| December 5 – December 19 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| December 19 – January 2 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| January 16 – January 30 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| February 13 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by September 20 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 29 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| December 13 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 96001 is 7 miles from Whiskeytown Rsvr, CA, which stands at 1,295 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 96001 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.