Chico, Washington Weather
Rufous Hummingbirds Arrive. Day 78 of spring. Read this microseason across nine climate regions →
Chico weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast13%—65°53°—
- FridayJun 5Drizzle23%0.02″59°47°-6°
- SaturdayJun 6Light Showers88%0.03″56°45°-3°
- SundayJun 7Overcast——65°44°+9°
- MondayJun 8Overcast45%—71°42°+6°
- TuesdayJun 9Overcast56%—78°44°+7°
- WednesdayJun 10Overcast39%—64°45°-14°
AQI 35 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 5.4 µg/m³ (AQI 30) with a 0.69 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in calm 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 5.4 µg/m³ (AQI 30) 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).
The higher the clouds, the finer the weather.
- Moonrise
- 7:37 AM
- Moonset
- 5:04 PM
- In sign
- ♒︎ Aquarius
Rufous Hummingbirds Arrive
Chico at a glance
- Today vs. normal: 12°F below the seasonal normal for this latitude
- Last frost: June 1 (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 — Chico
SPC has placed Chico 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
Chico's warmest month is August (~66°F mean) and its coldest is December (~40°F). Rainfall peaks in December (9.9 inches) and bottoms out in July (0.8 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 41° | 9.3″ | 14 |
| February | 42° | 5.8″ | 10 |
| March | 46° | 6.4″ | 12 |
| April | 50° | 3.9″ | 9 |
| May | 56° | 2.4″ | 6 |
| June | 61° | 1.6″ | 5 |
| July | 66° | 0.8″ | 2 |
| August | 66° | 1.1″ | 2 |
| September | 62° | 1.8″ | 5 |
| October | 53° | 5.1″ | 9 |
| November | 45° | 8.8″ | 13 |
| December | 40° | 9.9″ | 14 |
Regional context
Chico sits within a warm-summer Mediterranean climate region — a cohort that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Seattle, WA, Spokane, WA, Kennewick, WA, Bremerton, WA, Tacoma, WA.
Frequently asked
- When does it freeze in Chico?
- Chico's last spring frost typically falls around mid-May, and the first fall frost arrives around mid-October.
- What is the rainy season in Chico?
- December is the wettest month with about 9.9 inches of rain on average; the city receives roughly 57 inches annually.
- What is the warmest month in Chico?
- August is typically warmest, averaging about 66°F.
- What is the coldest month in Chico?
- December is typically coldest, averaging about 40°F.
- When can I start a vegetable garden in Chico?
- 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 Chico get?
- Chico averages about 102 rainy days per year.
- What hardiness zone is Chico?
- Chico'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
Chico, Washington sits in a warm-summer Mediterranean climate zone. January means hover near 41°F while July averages 66°F — a 24°F seasonal swing.
Across the year, Chico receives about 57 inches of precipitation spread over roughly 102 rainy days.
The rhythm of the year is set by latitude (47.6°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.