Weather in Portland, Oregon
Shoots and Sprouts Rise in Ranks. Day 59 of spring. Read this microseason across nine climate regions →
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 12:41 PM
- Moonset
- 4:19 AM
- In sign
- ♉︎ Taurus
Shoots and Sprouts Rise in Ranks
Portland at a glance
- Today vs. normal: NaN°F below the seasonal normal for this latitude
- Last frost: May 19 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Cool-season window is open
As of May 17, the cool-season window is open or about to open. Direct-sow peas, lettuce, spinach, radishes, and brassicas now. Hold off on warm-season crops until 1–2 weeks after the last spring frost (around May).
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | — | — |
| May | lettuce, peas, spinach, radishes | lettuce, peas, radishes |
| June | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | tomatoes, peppers, beans, squash, fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | — | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
August brings Portland's warmest temperatures (~70°F mean), while December delivers the coldest (~42°F). December also marks the wettest period with 7.3 inches of rainfall, contrasting sharply with July's dry 0.4 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 42° | 6.4″ | 14 |
| February | 45° | 4.7″ | 10 |
| March | 48° | 4.8″ | 12 |
| April | 53° | 3.6″ | 11 |
| May | 59° | 2.6″ | 8 |
| June | 63° | 1.5″ | 5 |
| July | 69° | 0.4″ | 2 |
| August | 70° | 0.5″ | 2 |
| September | 65° | 1.6″ | 4 |
| October | 55° | 4.0″ | 9 |
| November | 47° | 6.6″ | 13 |
| December | 42° | 7.3″ | 14 |
Regional context
Portland belongs to the warm-summer Mediterranean climate region, sharing similar temperature ranges, seasonal patterns, and growing conditions with other nearby cities in this zone.
Similar climates: Eugene, OR, Salem, OR, Medford, OR, Bend, OR, Gresham, OR.
Naturalist notes
Late May brings the first blooms of Oregon grape, their bright yellow flower clusters emerging after the final spring frosts.
American robins begin their second nesting cycle in June, taking advantage of Portland's lengthening daylight hours.
Frequently asked
- When does it freeze in Portland?
- Portland's last spring frost typically occurs around mid-May, while the first fall frost returns around mid-October.
- What is the rainy season in Portland?
- December stands as the wettest month, averaging about 7.3 inches of rain, contributing to the city's annual total of roughly 44 inches.
- What is the warmest month in Portland?
- August typically records the warmest temperatures, averaging about 70°F.
- What is the coldest month in Portland?
- December typically brings the coldest weather, averaging about 42°F.
- When can I start a vegetable garden in Portland?
- Cool-season crops like peas and lettuce can be planted around the last spring frost in mid-May, while warm-season crops such as tomatoes and peppers should wait 1–2 weeks after.
- How many rainy days does Portland get?
- Portland experiences about 102 rainy days per year on average.
- What hardiness zone is Portland?
- Portland's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool can provide the current zone designation using the city ZIP code.
Climate
Portland, Oregon experiences a warm-summer Mediterranean climate. January temperatures typically hover near 42°F, while July averages 69°F — creating a 27°F seasonal swing.
Annual precipitation totals about 44 inches, falling across roughly 102 rainy days throughout the year.
Geography drives Portland's weather patterns through its latitude (45.5°N), proximity to large water bodies, and elevation. These factors determine what grows in the region, when frost occurs, and the daily weather patterns.