Weather in Rockford, Illinois
Roses open along the stoops. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Rain54%83°60°
- SundayMay 17Light Drizzle34%87°65°
- MondayMay 18Thunderstorm73%83°69°
- TuesdayMay 19Showers65%73°52°
- WednesdayMay 20Overcast—61°44°
- ThursdayMay 21Overcast—64°40°
- FridayMay 22Overcast—67°48°
- PM 2.5
- 5.3 μg/m³
- PM 10
- 6.7 μg/m³
- NO₂
- 4.2 μg/m³
- Ozone
- 110.0 μg/m³
- UV Index
- 0.0 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 10:37 AM
- Moonset
- 1:44 AM
- In sign
- ♉︎ Taurus
Roses open along the stoops
Rockford at a glance
- Today vs. normal: 7°F above the seasonal normal for this latitude
- Last frost: April 30 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Cool-season window is open
As of May 17, the cool-season window is open or about to open. Direct-sow peas, lettuce, spinach, radishes, and brassicas now. Hold off on warm-season crops until 1–2 weeks after the last spring frost (around May).
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.