Weather in Springfield, Illinois
Roses open on the Piedmont edge. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Rain61%76°65°
- SundayMay 17Overcast12%86°64°
- MondayMay 18Light Showers60%79°68°
- TuesdayMay 19Light Showers80%78°59°
- WednesdayMay 20Overcast50%66°49°
- ThursdayMay 21Overcast—66°47°
- FridayMay 22Overcast12%62°55°
- PM 2.5
- 5.7 μg/m³
- PM 10
- 6.2 μg/m³
- NO₂
- 7.7 μg/m³
- Ozone
- 65.0 μg/m³
- UV Index
- 0.0 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 10:49 AM
- Moonset
- 1:36 AM
- In sign
- ♊︎ Gemini
Roses open on the Piedmont edge
Springfield at a glance
- Today vs. normal: 7°F below the seasonal normal for this latitude
- Last frost: April 15 (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
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
July brings Springfield's peak heat with average temperatures around 76°F, while January delivers the year's coldest conditions at roughly 27°F. Precipitation follows its own calendar, with May bringing the heaviest rainfall at 5.1 inches and January recording the lightest at 2.2 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 27° | 2.2″ | 5 |
| February | 31° | 2.2″ | 5 |
| March | 42° | 3.0″ | 7 |
| April | 53° | 4.1″ | 7 |
| May | 63° | 5.1″ | 9 |
| June | 73° | 5.0″ | 7 |
| July | 76° | 4.4″ | 7 |
| August | 74° | 2.9″ | 5 |
| September | 67° | 3.1″ | 5 |
| October | 55° | 3.1″ | 6 |
| November | 43° | 3.1″ | 6 |
| December | 33° | 2.3″ | 6 |
Regional context
Springfield falls within the humid subtropical climate region, sharing temperature ranges, seasonal rhythms, and growing conditions with other nearby cities in this climate classification.
Similar climates: Peoria, IL, Champaign, IL, Bloomington, IL, Alton, IL, Decatur, IL.
Naturalist notes
Late May brings the distinctive calls of red-winged blackbirds defending territory in Springfield's wetlands and marshy areas.
By early June, native prairie grasses like big bluestem begin their rapid growth phase across central Illinois grasslands.
Frequently asked
- When does it freeze in Springfield?
- Springfield typically sees its last spring frost around mid-April, while the first fall frost usually arrives around mid-November.
- What is the rainy season in Springfield?
- May stands as the wettest month, delivering about 5.1 inches of rain on average, while Springfield's total annual precipitation reaches roughly 40 inches.
- What is the warmest month in Springfield?
- July typically records the warmest temperatures, with averages around 76°F.
- What is the coldest month in Springfield?
- January brings the coldest conditions, averaging about 27°F.
- When can I start a vegetable garden in Springfield?
- Cool-season crops like peas and lettuce can be planted around the last spring frost in mid-April, while warm-season crops such as tomatoes and peppers should wait 1–2 weeks after that date.
- How many rainy days does Springfield get?
- Springfield experiences approximately 75 rainy days per year.
- What hardiness zone is Springfield?
- Springfield's USDA hardiness zone depends on its lowest average winter temperatures; the USDA's online lookup tool can provide the current zone designation using the city ZIP code.
Climate
Springfield, Illinois experiences a humid subtropical climate zone. Winter temperatures in January typically hover near 27°F, while July brings averages around 76°F — creating a 49°F seasonal swing.
Annual precipitation totals approximately 40 inches, distributed across roughly 75 rainy days throughout the year.
Geography plays the defining role in Springfield's weather patterns. The city's latitude at 39.8°N, proximity to large water bodies, and elevation combine to determine growing seasons, frost timing, and daily weather conditions.