Rockford, Illinois Weather
Fireflies rise from the lawn. Day 77 of spring. Read this microseason across nine climate regions →
Rockford weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——88°57°—
- FridayJun 5Heavy Rain64%1.4″76°68°-12°
- SaturdayJun 6Drizzle44%—83°68°+7°
- SundayJun 7Light Showers19%—80°66°-3°
- MondayJun 8Showers67%0.07″72°65°-8°
- TuesdayJun 9Light Showers52%—87°69°+15°
- WednesdayJun 10Light Showers22%—87°70°0°
Ozone at AQI 85 — peak already passed at 1 PM under clear skies. AQI up 46 in the last 6 hours — air quality is degrading. Levels should ease through evening.
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 85 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 85
- UV peak
- 0.9 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 85
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
- 4:33 AM
- Moonset
- 1:51 PM
- In sign
- ♒︎ Aquarius
Fireflies rise from the lawn
Rockford at a glance
- Today vs. normal: 13°F above the seasonal normal for this latitude
- Last frost: April 30 (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 — Rockford
SPC has placed Rockford in the Marginal Risk category for severe thunderstorms tomorrow.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWMRGLMarginal Risk
- DAY 3TSTMGeneral Thunderstorms
Isolated severe storms possible. Limited threat for hail or damaging wind.
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
July brings Rockford's warmest temperatures at around 74°F mean, while January delivers the coldest at about 22°F. Rain follows a different pattern, peaking in June at 5.2 inches and dropping to just 1.6 inches in January.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 22° | 1.6″ | 4 |
| February | 26° | 1.6″ | 4 |
| March | 37° | 2.4″ | 5 |
| April | 49° | 3.8″ | 7 |
| May | 60° | 4.2″ | 8 |
| June | 70° | 5.2″ | 8 |
| July | 74° | 3.8″ | 6 |
| August | 72° | 4.2″ | 6 |
| September | 64° | 3.6″ | 5 |
| October | 52° | 2.6″ | 5 |
| November | 39° | 2.3″ | 5 |
| December | 27° | 1.9″ | 5 |
Regional context
The city falls within a warm-summer humid continental climate region. Other nearby cities in this zone experience similar temperature ranges, seasonal patterns, and growing conditions.
Similar climates: Chicago, IL, Round Lake Beach, IL, Aurora, IL, Naperville, IL, Joliet, IL.
Naturalist notes
Late May brings the return of ruby-throated hummingbirds to Rockford's gardens and woodlands.
Wild columbine typically begins blooming in forest edges and shaded areas during the final weeks of May.
Frequently asked
- When does it freeze in Rockford?
- Spring's final frost usually occurs around mid-May in Rockford, while the first fall frost returns around mid-October.
- What is the rainy season in Rockford?
- June stands as the wettest month, delivering about 5.2 inches of rain on average. The city's annual total reaches roughly 37 inches.
- What is the warmest month in Rockford?
- July typically records the highest temperatures, averaging about 74°F.
- What is the coldest month in Rockford?
- January brings the year's coldest weather, averaging about 22°F.
- When can I start a vegetable garden in Rockford?
- Cool-season crops like peas and lettuce can go into the ground around the last spring frost in mid-May. Warm-season plants such as tomatoes and peppers should wait 1–2 weeks after that date.
- How many rainy days does Rockford get?
- Rockford sees precipitation on about 69 days per year on average.
- What hardiness zone is Rockford?
- The city's USDA hardiness zone depends on its lowest average winter temperature. Use the USDA's online lookup tool with Rockford's ZIP code for the current zone designation.
Climate
Rockford, Illinois experiences a warm-summer humid continental climate. January temperatures hover near 22°F while July averages 74°F, creating a 52°F seasonal swing.
Annual precipitation totals about 37 inches, falling across roughly 69 rainy days throughout the year.
Geography drives the local weather patterns. The city's latitude at 42.3°N, proximity to large water bodies, and elevation determine what grows here, when frost threatens, and how daily weather unfolds.