Portland, Oregon Weather
Rufous Hummingbirds Arrive. Day 77 of spring. Read this microseason across nine climate regions →
Portland weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——71°52°—
- FridayJun 5Overcast15%—62°50°-9°
- SaturdayJun 6Drizzle83%0.03″63°46°+1°
- SundayJun 7Heavy Drizzle13%0.08″67°45°+4°
- MondayJun 8Light Showers59%0.39″59°48°-8°
- TuesdayJun 9Light Drizzle56%—59°48°0°
- WednesdayJun 10Light Drizzle45%—60°49°+1°
AQI 29 (Good), driven by Ozone. AQI down 13 over the last 6 hours (steady decline since this morning).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 11 AM.
What's driving it
PM × Wind × Precip
PM2.5 at 4.7 µg/m³ (AQI 26) with a 0.69 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.69
- Wind
- calm
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 7:02 AM
- Moonset
- 4:00 PM
- In sign
- ♑︎ Capricorn
Rufous Hummingbirds Arrive
Portland at a glance
- Today vs. normal: 15°F below the seasonal normal for this latitude
- Last frost: May 19 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 4, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Portland
SPC has placed Portland in the General Thunderstorms category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWNONENo severe risk
- DAY 3TSTMGeneral Thunderstorms
Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
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.