USDA Hardiness Zone 9a
Frost Dates for 97439 — Florence, Oregon
NOAA 1991–2020 normals from Florence #2, OR (75 ft), under a mile southwest.
Updated
In Florence, the last spring frost (32°F) is around April 10 in half of years and has passed by May 5 in nine years out of ten. The first fall frost comes around November 15, as early as October 23 one year in ten, leaving a typical freeze-free season of 220 days (NOAA, Florence #2, OR).
- Last spring frost
- April 10
- First fall frost
- November 15
- Growing season
- 220 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
- 26%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
7 of 27 observed
NOAA normal
Frost risk by date in Florence
Half of springs at Florence #2, OR see their last 32°F night by April 10; only one in ten is past it by March 6, and one in ten still has one after May 5. Planting tender crops after April 22 leaves a 30% risk of a frost on them, after April 29 20%, and after May 5 10%. The 25 days between the even-odds date and the one-in-ten date is wider than at 68% of the 103 Oregon 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 15 in half of years, as early as October 23 one year in ten, and holds off past December 13 one year in ten. A hard freeze of 28°F follows 27 days later, around December 12; in spring the one-in-ten date for 28°F is April 1, 34 days before the 32°F one. The freeze-free season lasts 220 days in a typical year, longer than at 63% of the 103 Oregon stations; it reaches 263 days one year in ten and falls short of 185 one year in ten. On average 32 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 28 days longer, to about May 8, and return around October 15. A 24°F night is unusual: 41% of winters had one.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 18 | Apr 26 | Apr 30 | May 4 | May 8 | May 13 | May 17 | May 23 | May 30 |
| 32°F | Mar 6 | Mar 20 | Mar 29 | Apr 3 | Apr 10 | Apr 16 | Apr 22 | Apr 29 | May 5 |
| 28°F93% of yrs | Dec 25 | Jan 27 | Feb 12 | Feb 19 | Feb 26 | Mar 5 | Mar 14 | Mar 24 | Apr 1 |
| 24°F41% of yrs | too rare for a date | ||||||||
| 20°F11% of yrs | too rare for a date | ||||||||
| 16°F4% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 17 | Sep 27 | Oct 3 | Oct 10 | Oct 15 | Oct 21 | Oct 26 | Oct 31 | Nov 9 |
| 32°F | Oct 23 | Oct 31 | Nov 6 | Nov 10 | Nov 15 | Nov 22 | Nov 29 | Dec 4 | Dec 13 |
| 28°F93% of yrs | Nov 12 | Nov 23 | Dec 1 | Dec 6 | Dec 12 | Dec 21 | Jan 3 | Jan 29 | Feb 17 |
| 24°F41% of yrs | too rare for a date | ||||||||
| 20°F11% of yrs | too rare for a date | ||||||||
| 16°F4% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Florence #2, OR, 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 97439 →Compare Florence with another place →
Weather by month in Florence
July is the warmest month at Florence #2, OR, averaging 68°F by day and 50°F at night; December is the coldest at 48°F and 37°F. From June to September the chance of a 32°F night stays under 10% each month.
Warmth for growing adds up to 1,122 growing degree days a year (base 50°F), fewer than at 98% of the 103 Oregon stations. 24% of them (270) have built up by the end of June, and July adds the most, 270. Precipitation totals 75.8 inches a year, most in December (12.5") and least in July (0.5"); May to September bring 14% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 49 | 39 | 10.2 | 79% | 7 | 5 |
| Feb | 51 | 37 | 9.4 | 89% | 7 | 6 |
| Mar | 53 | 39 | 9.3 | 77% | 6 | 11 |
| Apr | 56 | 40 | 6.4 | 58% | 2 | 20 |
| May | 60 | 44 | 3.9 | 16% | 1 | 78 |
| Jun | 64 | 46 | 2.9 | 0% | 0 | 150 |
| Jul | 68 | 50 | 0.5 | 0% | 0 | 270 |
| Aug | 67 | 49 | 1.1 | 0% | 0 | 259 |
| Sep | 66 | 47 | 2.3 | 0% | 0 | 194 |
| Oct | 61 | 44 | 6.0 | 21% | 1 | 100 |
| Nov | 53 | 40 | 11.3 | 66% | 2 | 25 |
| Dec | 48 | 37 | 12.5 | 88% | 7 | 4 |
Monthly normals 1991–2020 at Florence #2, OR (75 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, Yachats, OR, 22 miles north of Florence, has a last frost 50 days earlier (February 19), a first frost 26 days later (December 11), a season 83 days longer.
When it snows in Florence, Oregon
Measurable snow is rare here: only 7 of 27 winters from 1991 to 2020 recorded 0.1 inch or more at Honeyman Sp, OR, 5.7 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 97439
| When | What to do |
|---|---|
| January 30 – February 13 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 13 – February 27 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 13 – March 27 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 10 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 23 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 1 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 15 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 97439 is under a mile from Florence #2, OR, which stands at 75 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 97439 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.
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.