USDA Hardiness Zone 8b
Frost Dates for 97132 — Newberg, Oregon
NOAA 1991–2020 normals from Rex 1 S, OR (515 ft), 3 miles east.
Updated
In Newberg, the last spring frost (32°F) is around March 21 in half of years and has passed by April 19 in nine years out of ten. The first fall frost comes around November 22, as early as November 4 one year in ten, leaving a typical freeze-free season of 241 days (NOAA, Rex 1 S, OR).
- Last spring frost
- March 21
- First fall frost
- November 22
- Growing season
- 241 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
- 37%
- Snow per year
- 1"
median, 1991–2020
median, 1991–2020
10 of 27 observed
NOAA normal
Frost risk by date in Newberg
Half of springs at Rex 1 S, OR see their last 32°F night by March 21; only one in ten is past it by February 23, and one in ten still has one after April 19. Planting tender crops after April 2 leaves a 30% risk of a frost on them, after April 10 20%, and after April 19 10%. The 29 days between the even-odds date and the one-in-ten date is wider than at 82% 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 22 in half of years, as early as November 4 one year in ten, and holds off past December 12 one year in ten. A hard freeze of 28°F follows 18 days later, around December 10; in spring the one-in-ten date for 28°F is March 11, 39 days before the 32°F one. The freeze-free season lasts 241 days in a typical year, longer than at 78% of the 103 Oregon stations; it reaches 275 days one year in ten and falls short of 211 one year in ten. On average 43 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 31 days longer, to about April 21, and return around November 3. Nights of 24°F, cold enough to damage hardier plants, come in 70% of winters and 16°F in 8%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 30 | Apr 5 | Apr 11 | Apr 16 | Apr 21 | Apr 26 | Apr 28 | May 1 | May 6 |
| 32°F | Feb 23 | Mar 1 | Mar 9 | Mar 15 | Mar 21 | Mar 28 | Apr 2 | Apr 10 | Apr 19 |
| 28°F97% of yrs | Jan 3 | Jan 21 | Feb 2 | Feb 9 | Feb 15 | Feb 20 | Feb 25 | Mar 2 | Mar 11 |
| 24°F70% of yrs | Dec 11 | Dec 23 | Jan 1 | Jan 9 | Jan 16 | Jan 26 | Feb 1 | Feb 12 | Feb 19 |
| 20°F30% of yrs | too rare for a date | ||||||||
| 16°F8% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 20 | Oct 25 | Oct 29 | Oct 31 | Nov 3 | Nov 7 | Nov 11 | Nov 16 | Nov 22 |
| 32°F | Nov 4 | Nov 9 | Nov 12 | Nov 17 | Nov 22 | Nov 25 | Nov 29 | Dec 4 | Dec 12 |
| 28°F97% of yrs | Nov 15 | Nov 25 | Dec 1 | Dec 6 | Dec 10 | Dec 16 | Dec 22 | Dec 30 | Jan 12 |
| 24°F70% of yrs | Dec 1 | Dec 7 | Dec 12 | Dec 19 | Dec 27 | Jan 1 | Jan 9 | Jan 22 | Feb 7 |
| 20°F30% of yrs | too rare for a date | ||||||||
| 16°F8% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Rex 1 S, 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 97132 →Compare Newberg with another place →
Weather by month in Newberg
August is the warmest month at Rex 1 S, OR, averaging 81°F by day and 56°F at night; December is the coldest at 44°F and 34°F. A freezing night is all but certain in every month from December to February (a 90% chance or more). From May to October the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 71% of years and April still brings one in 33% of years.
Warmth for growing adds up to 2,381 growing degree days a year (base 50°F), more than at 63% of the 103 Oregon stations. 29% of them (680) have built up by the end of June, and August adds the most, 575. Precipitation totals 44.5 inches a year, most in December (7.4") and least in July (0.4"); May to September bring 15% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 45 | 35 | 6.4 | 95% | 11 | 2 |
| Feb | 50 | 36 | 4.6 | 92% | 9 | 7 |
| Mar | 55 | 38 | 4.8 | 71% | 5 | 30 |
| Apr | 61 | 41 | 3.6 | 33% | 1 | 77 |
| May | 66 | 47 | 2.6 | 0% | 0 | 217 |
| Jun | 72 | 51 | 1.6 | 0% | 0 | 347 |
| Jul | 81 | 56 | 0.4 | 0% | 0 | 562 |
| Aug | 81 | 56 | 0.6 | 0% | 0 | 575 |
| Sep | 75 | 52 | 1.6 | 0% | 0 | 403 |
| Oct | 62 | 45 | 4.2 | 6% | 1 | 142 |
| Nov | 51 | 39 | 6.7 | 70% | 4 | 18 |
| Dec | 44 | 34 | 7.4 | 98% | 12 | 2 |
Monthly normals 1991–2020 at Rex 1 S, OR (515 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, Aurora State Airport, OR, 11 miles southeast of Newberg and 319 feet lower, has a last frost 5 days earlier (March 16), a first frost 8 days earlier (November 14), a season 1 day longer.
When it snows in Newberg, Oregon
Measurable snow is rare here: only 10 of 27 winters from 1991 to 2020 recorded 0.1 inch or more at Rex 1 S, OR, 2.9 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 97132
| When | What to do |
|---|---|
| January 10 – January 24 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| January 24 – February 7 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| February 21 – March 7 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| March 21 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 30 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 8 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 22 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 97132 is 3 miles from Rex 1 S, OR, which stands at 515 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 97132 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.