Renton, Washington Weather
Rufous Hummingbirds Arrive. Day 78 of spring. Read this microseason across nine climate regions →
Renton weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——70°54°—
- FridayJun 5Heavy Drizzle38%0.06″61°49°-9°
- SaturdayJun 6Light Showers81%0.02″58°47°-3°
- SundayJun 7Light Drizzle——65°46°+7°
- MondayJun 8Overcast52%—71°46°+6°
- TuesdayJun 9Overcast52%—78°48°+7°
- WednesdayJun 10Overcast34%—63°51°-15°
AQI 38 (Good), driven by PM2.5. AQI up 6 over the last 6 hours (gradual rise). PM2.5 at 6.2 µg/m³, PM10 at 7.7 µg/m³ — typical background levels with no transport signature.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 32. Overcast through the UV peak window (cloud cover ~78%) — afternoon ozone should stay flat.
- Present
- AQI 32
- UV peak
- 0.0 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 4
PM × Wind × Precip
PM2.5 at 6.2 µg/m³, PM10 at 7.7 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.81
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- background
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).
The higher the clouds, the finer the weather.
- Moonrise
- 7:34 AM
- Moonset
- 5:02 PM
- In sign
- ♒︎ Aquarius
Rufous Hummingbirds Arrive
Renton at a glance
- Today vs. normal: 8°F below the seasonal normal for this latitude
- Last frost: May 31 (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 5, 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 — Renton
SPC has placed Renton in the General Thunderstorms category for severe thunderstorms tomorrow.
- TODAYNONENo severe risk
- TOMORROWTSTMGeneral Thunderstorms
- 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
Renton's warmest month is August (~67°F mean) and its coldest is December (~42°F). Rainfall peaks in November (5.8 inches) and bottoms out in July (0.8 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 42° | 5.1″ | 12 |
| February | 43° | 3.5″ | 9 |
| March | 47° | 3.9″ | 11 |
| April | 51° | 3.0″ | 9 |
| May | 57° | 2.2″ | 6 |
| June | 61° | 1.6″ | 5 |
| July | 67° | 0.8″ | 2 |
| August | 67° | 1.0″ | 3 |
| September | 62° | 1.7″ | 5 |
| October | 54° | 3.6″ | 9 |
| November | 46° | 5.8″ | 12 |
| December | 42° | 5.5″ | 12 |
Regional context
Renton belongs to a warm-summer Mediterranean climate region — a group that shares comparable temperature ranges, seasonal patterns, and growing conditions with neighboring cities.
Similar climates: Seattle, WA, Spokane, WA, Kennewick, WA, Bremerton, WA, Tacoma, WA.
Naturalist notes
By late spring, bigleaf maples along the Cedar River are fully leafed out and shedding winged samaras that spiral down onto trails and sidewalks.
Western tiger swallowtails appear in residential gardens through late May and June, nectaring on lilacs and rhododendrons as the days stretch toward the solstice.
Frequently asked
- When does it freeze in Renton?
- Renton's last spring frost typically falls around mid-May, and the first fall frost arrives around mid-October.
- What is the rainy season in Renton?
- November is the wettest month with about 5.8 inches of rain on average; the city receives roughly 38 inches annually.
- What is the warmest month in Renton?
- August is typically warmest, averaging about 67°F.
- What is the coldest month in Renton?
- December is typically coldest, averaging about 42°F.
- When can I start a vegetable garden in Renton?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-May); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Renton get?
- Renton averages about 95 rainy days per year.
- What hardiness zone is Renton?
- Renton's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
Renton, Washington falls under a warm-summer Mediterranean climate classification. January temperatures hold near 42°F, while July averages 67°F — a seasonal swing of 24°F.
Throughout the year, the city receives roughly 38 inches of precipitation distributed across about 95 rainy days.
Latitude (47.5°N), nearby water, and elevation set the cadence of the year. Together they shape what can be grown, when frost is likely, and the daily weather pattern.