USDA Hardiness Zone 8b
Frost Dates for 97537 — Rogue River, Oregon
NOAA 1991–2020 normals from Grants Pass, OR (932 ft), 11 miles southwest.
Updated
In Rogue River, the last spring frost (32°F) is around April 8 in half of years and has passed by May 1 in nine years out of ten. The first fall frost comes around October 28, as early as October 8 one year in ten, leaving a typical freeze-free season of 201 days (NOAA, Grants Pass, OR).
- Last spring frost
- April 8
- First fall frost
- October 28
- Growing season
- 201 days
- Hardiness zone
- 8b
50% probability
50% probability
freeze-free, 50%
15 to 20°F (-9.4 to -6.7°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 12%
- Snow per year
- 0.3"
median, 1991–2020
median, 1991–2020
2 of 17 observed
NOAA normal
Frost risk by date in Rogue River
Half of springs at Grants Pass, OR see their last 32°F night by April 8; only one in ten is past it by March 15, and one in ten still has one after May 1. Planting tender crops after April 19 leaves a 30% risk of a frost on them, after April 24 20%, and after May 1 10%. The 23 days between the even-odds date and the one-in-ten date is wider than at 56% 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 October 28 in half of years, as early as October 8 one year in ten, and holds off past November 24 one year in ten. A hard freeze of 28°F follows 19 days later, around November 16; in spring the one-in-ten date for 28°F is April 5, 26 days before the 32°F one. The freeze-free season lasts 201 days in a typical year, longer than at 51% of the 103 Oregon stations; it reaches 234 days one year in ten and falls short of 172 one year in ten. On average 65 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 24 days longer, to about May 2, and return around October 11. Nights of 24°F, cold enough to damage hardier plants, come in 83% of winters and 16°F in 11%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 14 | Apr 20 | Apr 26 | Apr 30 | May 2 | May 6 | May 13 | May 20 | May 30 |
| 32°F | Mar 15 | Mar 26 | Mar 31 | Apr 3 | Apr 8 | Apr 13 | Apr 19 | Apr 24 | May 1 |
| 28°F | Jan 19 | Feb 14 | Feb 22 | Feb 28 | Mar 8 | Mar 16 | Mar 23 | Mar 29 | Apr 5 |
| 24°F83% of yrs | Dec 6 | Dec 23 | Jan 3 | Jan 16 | Jan 29 | Feb 12 | Feb 20 | Feb 28 | Mar 8 |
| 20°F40% of yrs | too rare for a date | ||||||||
| 16°F11% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 23 | Sep 30 | Oct 3 | Oct 7 | Oct 11 | Oct 15 | Oct 19 | Oct 24 | Oct 31 |
| 32°F | Oct 8 | Oct 15 | Oct 19 | Oct 23 | Oct 28 | Nov 1 | Nov 6 | Nov 13 | Nov 24 |
| 28°F | Oct 22 | Oct 28 | Nov 2 | Nov 9 | Nov 16 | Nov 25 | Dec 2 | Dec 11 | Dec 27 |
| 24°F83% of yrs | Nov 3 | Nov 16 | Nov 28 | Dec 3 | Dec 11 | Dec 21 | Jan 2 | Jan 14 | Feb 6 |
| 20°F40% of yrs | too rare for a date | ||||||||
| 16°F11% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Grants Pass, 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 97537 →Compare Rogue River with another place →
Weather by month in Rogue River
July is the warmest month at Grants Pass, OR, averaging 91°F by day and 56°F at night; December is the coldest at 46°F and 35°F. A freezing night is all but certain in every month from December to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 64% of years.
Warmth for growing adds up to 3,106 growing degree days a year (base 50°F), more than at 94% of the 103 Oregon stations. 31% of them (971) have built up by the end of June, and July adds the most, 725. Precipitation totals 31.6 inches a year, most in December (6.6") and least in August (0.3"); May to September bring 11% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 48 | 35 | 5.1 | 92% | 13 | 4 |
| Feb | 54 | 36 | 4.0 | 91% | 12 | 14 |
| Mar | 60 | 37 | 3.7 | 93% | 10 | 45 |
| Apr | 65 | 40 | 2.3 | 64% | 4 | 120 |
| May | 74 | 46 | 1.4 | 10% | 1 | 312 |
| Jun | 81 | 51 | 0.7 | 0% | <1 | 476 |
| Jul | 91 | 56 | 0.4 | 0% | 0 | 725 |
| Aug | 91 | 55 | 0.3 | 0% | 0 | 705 |
| Sep | 84 | 48 | 0.6 | 1% | 1 | 483 |
| Oct | 70 | 41 | 2.1 | 58% | 5 | 188 |
| Nov | 54 | 39 | 4.4 | 85% | 7 | 29 |
| Dec | 46 | 35 | 6.6 | 96% | 13 | 5 |
Monthly normals 1991–2020 at Grants Pass, OR (932 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, Sexton Summit, OR, 12 miles northwest of Rogue River and 2,900 feet higher, has a last frost 38 days later (May 16), a first frost 2 days later (October 30), a season 37 days shorter.
When it snows in Rogue River, Oregon
Measurable snow is rare here: only 2 of 17 winters from 1991 to 2020 recorded 0.1 inch or more at Applegate, OR, 19.5 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 97537
| When | What to do |
|---|---|
| January 28 – February 11 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 11 – February 25 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 11 – March 25 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 8 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 5 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 14 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 28 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 97537 is 11 miles from Grants Pass, OR, which stands at 932 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 97527 (Grants Pass). The 2023 USDA Plant Hardiness Zone Map lists ZIP 97537 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°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.