North Willamette Experiment Station, Oregon climate: Climate normals at a NOAA weather station
North Willamette Experiment Station's normal year runs from 36°F December nights to 82°F August afternoons, with 42.4 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 12.2°C, December lows of 2°C, August highs of 28°C, 1,076 mm of precipitation a year.
- NOAA stationNorth Willamette Experiment Station
- Station IDUSC00356151
- Location45.28°N 122.75°W
- Elevation150 ft (46 m)
On October 23, the normal high in North Willamette Experiment Station is 60°F and the normal low 43°F, and the chance of measurable rain or snow is 46%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for North Willamette Experiment Station.
- Jan 47° 36°
- Feb 52° 37°
- Mar 56° 39°
- Apr 60° 42°
- May 68° 47°
- Jun 74° 52°
- Jul 82° 56°
- Aug 82° 55°
- Sep 76° 51°
- Oct 64° 45°
- Nov 52° 39°
- Dec 47° 36°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at North Willamette Experiment Station each month?
August is the warmest month, with normal highs of 82°F; December the coldest, with normal lows of 36°F. The most precipitation falls in December (6.60 in), the least in July (0.45 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 47°F | 36°F | 41.8°F | 6.12 | 19 | <1 | 10 | 9 h 10 min |
| February | 52°F | 37°F | 44.1°F | 4.20 | 15 | <1 | 8 | 10 h 20 min |
| March | 56°F | 39°F | 47.3°F | 4.92 | 17 | <1 | 4 | 11 h 50 min |
| April | 60°F | 42°F | 51.2°F | 3.28 | 17 | <1 | 2 | 13 h 30 min |
| May | 68°F | 47°F | 57.4°F | 2.44 | 13 | 1 | <1 | 14 h 50 min |
| June | 74°F | 52°F | 62.7°F | 1.59 | 8 | 2 | <1 | 15 h 40 min |
| July | 82°F | 56°F | 68.6°F | 0.45 | 3 | 6 | <1 | 15 h 20 min |
| August | 82°F | 55°F | 68.7°F | 0.53 | 3 | 6 | <1 | 14 h 10 min |
| September | 76°F | 51°F | 63.8°F | 1.73 | 6 | 3 | <1 | 12 h 40 min |
| October | 64°F | 45°F | 54.0°F | 4.27 | 13 | <1 | 1 | 11 h |
| November | 52°F | 39°F | 45.8°F | 6.25 | 19 | <1 | 7 | 9 h 30 min |
| December | 47°F | 36°F | 41.3°F | 6.60 | 18 | <1 | 13 | 8 h 50 min |
| Year (annual) | 63°F | 45°F | 53.9°F | 42.38 | 152 | 16 | 45 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 8°C | 2°C | 5.4°C | 155 mm |
| February | 11°C | 3°C | 6.7°C | 107 mm |
| March | 13°C | 4°C | 8.5°C | 125 mm |
| April | 16°C | 6°C | 10.7°C | 83 mm |
| May | 20°C | 8°C | 14.1°C | 62 mm |
| June | 23°C | 11°C | 17.1°C | 40 mm |
| July | 28°C | 13°C | 20.3°C | 11 mm |
| August | 28°C | 13°C | 20.4°C | 13 mm |
| September | 25°C | 11°C | 17.7°C | 44 mm |
| October | 18°C | 7°C | 12.2°C | 108 mm |
| November | 11°C | 4°C | 7.7°C | 159 mm |
| December | 8°C | 2°C | 5.2°C | 168 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Rex (1 mi S) (8 miles away), gets 1 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00356151; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
Which months are mildest at North Willamette Experiment Station?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, July has the fewest days with rain (3).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00356151.
When is the last frost at North Willamette Experiment Station?
In North Willamette Experiment Station, the last spring frost (32°F) comes after March 18 in half of years and after April 10 in one year in ten; the first autumn frost comes before November 13 in half of years and before October 27 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- March 181 year in 10 after April 10; 9 in 10 after February 22
- First autumn frost, half of years before
- November 131 year in 10 before October 27; 9 in 10 before December 6
NOAA puts the median frost-free season at 243 days, and the season without a hard freeze (28°F) at 298 days.
A hard freeze (28°F) comes after February 13 in half of springs and before December 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts North Willamette Experiment Station in zone 8b in ZIP code 97070, the nearest ZIP area.
Frost dates for every NOAA station in Oregon · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00356151; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get at North Willamette Experiment Station?
In a normal year in North Willamette Experiment Station, 16 days a year reach 90°F (2 of them 100°F or more), 45 nights fall to 32°F or colder and 152 days bring measurable precipitation.
- Days at 90°F or more
- 16a normal year
- Days at 100°F or more
- 2a normal year
- Nights at 32°F or colder
- 45a normal year
- Days that stay below freezing
- 2high of 32°F or less
- Days with 0.01 inch of precipitation
- 152a normal year
The highest temperature in this station's record (since 1963) is 105°F, on August 18, 1977; the lowest is 0°F, on December 21, 1990.
The wettest calendar year on that record is 1996, with 74.10 in; the snowiest season is 1968–69, with 29.2 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00356151; records: ACIS (NOAA Regional Climate Centers), station USC00356151. Records use complete months only; a month missing more than three days is left out.
How sunny is it at North Willamette Experiment Station?
Over a year 70% of the sunlight that would reach the ground under clear skies gets through the clouds at North Willamette Experiment Station, 3.7 kWh per square metre a day. July is the sunniest month (83%) and December the cloudiest (52%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 54% | 1.2 |
| February | 60% | 2.1 |
| March | 59% | 3.0 |
| April | 63% | 4.3 |
| May | 68% | 5.4 |
| June | 70% | 6.0 |
| July | 83% | 6.8 |
| August | 83% | 5.8 |
| September | 78% | 4.3 |
| October | 67% | 2.6 |
| November | 56% | 1.4 |
| December | 52% | 1.0 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How many heating and cooling degree days does North Willamette Experiment Station record?
A normal year at North Willamette Experiment Station brings 4,409 heating degree days, 18% fewer than the median U.S. place (5,373), and 374 cooling degree days, 59% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,490 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 719 | 0 |
| February | 585 | 0 |
| March | 549 | 0 |
| April | 416 | 1 |
| May | 249 | 13 |
| June | 109 | 40 |
| July | 21 | 132 |
| August | 19 | 135 |
| September | 88 | 51 |
| October | 342 | 2 |
| November | 576 | 0 |
| December | 736 | 0 |
| Year (annual) | 4,409 | 374 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00356151. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
How does North Willamette Experiment Station's climate compare?
North Willamette Experiment Station is warmer than 83 of the 105 places with their own NOAA record in Oregon, and wetter than 58. Across the 7,247 U.S. stations with normals, its annual mean of 53.9°F is warmer than 57%.
In the Köppen classification computed from these normals, North Willamette Experiment Station is Csb: temperate, dry-summer, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near North Willamette Experiment Station share this climate record?
2 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Wilsonville, OR27,895 people · 2 mi NW
- Canby, OR18,027 people · 3 mi E
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about North Willamette Experiment Station's climate
What is the coldest month at North Willamette Experiment Station?
December, with a normal high of 47°F and a normal low of 36°F. The warmest is August (82°F by day, 55°F at night).
Does it snow at North Willamette Experiment Station?
Yes. NOAA publishes no 1991-2020 snowfall normal for the station; the nearest record that keeps one, Rex (1 mi S) (8 miles away), records 1 inches of snow in a normal year.
What is the rainiest month at North Willamette Experiment Station?
December, with 6.60 in of precipitation in a normal year; the driest is July with 0.45 in.
What plant hardiness zone is North Willamette Experiment Station in?
The USDA's 2023 map puts North Willamette Experiment Station in zone 8b in ZIP code 97070, the nearest ZIP area.
How late can frost come at North Willamette Experiment Station?
In half of years the last 32°F night comes after March 18; in one year in ten it comes after April 10. Waiting until April 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Oregon climateThe statewide normals and every place in the state
- Aurora, OR2 miles from this station, 54.8°F a year
- Rex (1 mi S), OR8 miles from this station, 53.0°F a year
- Oregon City, OR9 miles from this station, 55.4°F a year
- Beaverton, OR12 miles from this station, 53.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made