Portland, Oregon Weather
Fog locks the valleys. Day 93 of summer. Read this microseason across nine climate regions →
Portland weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 2:22 AM PDT · Open-Meteo
- TodaySep 21Clear——74°55°—
- TuesdaySep 22Overcast——70°53°-4°
- WednesdaySep 23Overcast——75°54°+5°
- ThursdaySep 24Showers37%0.41″65°55°-10°
- FridaySep 25Showers44%0.13″65°51°0°
- SaturdaySep 26Overcast——64°50°-1°
- SundaySep 27Overcast10%—73°54°+9°
Air quality now AQI 51 · Moderate
AQI 51 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 11.1 µg/m³ (AQI 55) with a 0.94 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in stagnant air, not road dust.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
PM × Wind × Precip
PM2.5 at 11.1 µg/m³ (AQI 55) with a 0.94 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in stagnant air, not road dust.
- PM2.5/PM10
- 0.94
- 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).
September dries up ditches or breaks down bridges.
- Moonrise
- —
- Moonset
- 1:17 AM
- In sign
- ♑︎ Capricorn
Fog locks the valleys
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Portland at a glance
- Today vs. normal: Today averages 65°F (high 74°F, low 55°F), 4°F above the 61°F normal for Sep 21
- Last frost: February 25 (1991–2020 median, NOAA station 4 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant beans, squash, fall brassicas, carrots; harvest tomatoes, peppers, beans, summer squash, winter squash
15-Day Forecast — Portland
- Mon75°55°0%
- Tue74°53°2%
- Wed75°54°0%
- Thu65°55°46%
- Fri65°51°54%
- Sat64°50°5%
- Sun73°54°11%
- Mon75°53°9%
- Tue79°54°7%
- Wed78°57°11%
- Thu76°58°14%
- Fri62°53°19%
- Sat65°49°16%
- Sun67°47°23%
- Mon65°48°20%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Portland
Interactive wind and temperature map centered on Portland — it loads in your browser. Open the full weather map.
Right now in the garden
Peak growing season
As of September 21, the growing season is at its peak — the first frost (around December 1) is weeks away. Fall transplants go in about 10–12 weeks before the first frost, September 8 to September 22 here. This city's planting calendar for September: plant beans, squash, fall brassicas, and carrots; harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Portland
Portland sits in Multnomah County, where the year’s longest day runs 15h 41m of daylight and its shortest just 8h 42m — a swing of +7h between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Portland is the state’s largest city. The nearest town Portland tracks is Salem, roughly 46 miles to the SSW.
Air quality in Portland
Air quality in Portland’s county has held roughly steady since 2020; its cleanest year on record was 2024 (median AQI 35). See the full air-quality history for Portland.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| February | lettuce, peas, spinach, radishes | radishes |
| March | lettuce, peas, spinach, radishes | lettuce, spinach, radishes |
| April | — | lettuce, peas, spinach, radishes |
| May | — | lettuce, peas, spinach, garlic |
| June | tomatoes, peppers, beans, squash | garlic |
| July | tomatoes, peppers, beans, squash | — |
| August | tomatoes, peppers, beans, squash | tomatoes, peppers, beans, summer squash |
| September | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| October | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| November | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| December | — | fall brassicas, carrots |
A year in weather
In Portland, August runs warmest near 69°F and January coldest around 39°F, while December is the wettest month (7.2 inches) and July the driest (0.3 inches).
| Month | Mean temp | Precip |
|---|---|---|
| January | 39° | 7.2″ |
| February | 41° | 5.5″ |
| March | 44° | 5.9″ |
| April | 50° | 3.9″ |
| May | 56° | 2.7″ |
| June | 62° | 1.7″ |
| July | 68° | 0.3″ |
| August | 69° | 0.5″ |
| September | 63° | 1.9″ |
| October | 53° | 5.7″ |
| November | 45° | 7.1″ |
| December | 39° | 7.2″ |
Regional context
Similar climates Maywood Park, OR, West Haven-Sylvan, OR, Raleigh Hills, OR
In Portland, modelled 1991-2020 normals (EC_Earth3P_HR model via Open-Meteo) put January near 39°F and July near 68°F — a 29°F seasonal arc — with about 49.7 inches of precipitation.
Cool-season fronts carry Portland's rain: December logs 7.2 inches, against July's 0.3 inches — winter does the heavy lifting in Portland. That groups Portland with places like Maywood Park, OR, West Haven-Sylvan, OR and Raleigh Hills, OR on the same cool-season storm track.
Around February 25, Portland sheds its freezing nights — peas, lettuce, spinach, and radishes go into Portland's beds. Portland's heat-lovers — tomatoes, peppers, squash — hold off until Portland's frost risk clears, 10-14 days on. The season ends by December 1 in Portland, once hard frosts set back in. That date is a median: Portland freezes sooner in half of years.
Similar climates: Maywood Park, OR, West Haven-Sylvan, OR, Raleigh Hills, OR, Milwaukie, OR, West Slope, OR.
Frequently asked
- When does it freeze in Portland?
- Portland's last spring frost lands near February 25, and in Portland the first fall frost follows around December 1.
- What is the rainy season in Portland?
- Rainfall in Portland peaks in December near 7.2 inches, out of about 50 inches annually.
- What is the warmest month in Portland?
- On average August tops the year in Portland at about 69°F.
- What is the coldest month in Portland?
- The coldest stretch in Portland falls in January, around 39°F on average.
- When can I start a vegetable garden in Portland?
- Around February 25, start frost-hardy crops in Portland; tomatoes and basil belong a fortnight later.
- What hardiness zone is Portland?
- Since January in Portland averages 39°F, Portland's USDA zone follows that floor — confirm it by ZIP.
- What is the 10-day forecast for Portland?
- Portland's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Portland?
- See this week's day-by-day rain chances for Portland in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Portland?
- Current conditions for Portland and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Portland forecast updated?
- The Portland forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Portland?
- Today's sunrise and sunset times for Portland are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Portland?
- The next few days in Portland's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Portland sits at 45.5°N; its climate zone is warm-summer Mediterranean (Köppen approximation).
ZIP codes in Portland
- 97201
- 97202
- 97203
- 97204
- 97205
- 97206
- 97207
- 97208
- 97209
- 97210
- 97211
- 97212
- 97213
- 97214
- 97215
- 97216
- 97217
- 97218
- 97219
- 97220
- 97221
- 97222
- 97223
- 97224
- 97225
- 97227
- 97228
- 97229
- 97230
- 97231
- 97232
- 97233
- 97236
- 97238
- 97239
- 97240
- 97242
- 97250
- 97251
- 97252
- 97253
- 97254
- 97256
- 97258
- 97266
- 97267
- 97280
- 97282
- 97283
- 97286
- 97290
- 97291
- 97292
- 97293
- 97294