Carlinville, Illinois Weather
Fireflies pulse through the magnolias. Day 78 of spring. Read this microseason across nine climate regions →
Carlinville weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Partly Cloudy——83°57°—
- FridayJun 5Overcast21%—87°67°+4°
- SaturdayJun 6Light Drizzle20%0.02″86°67°-1°
- SundayJun 7Showers43%0.02″84°68°-2°
- MondayJun 8Showers72%0.05″86°69°+2°
- TuesdayJun 9Thunderstorm46%—90°70°+4°
- WednesdayJun 10Thunderstorm16%—91°74°+1°
PM2.5 at 8.9 µg/m³, PM10 at 10.3 µg/m³ — typical background levels with no transport signature. AQI up 40 in the last 6 hours — air quality is degrading.
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 49. Overcast through the UV peak window (cloud cover ~100%) — afternoon ozone should stay flat.
- Present
- AQI 49
- UV peak
- 0.2 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 6
PM × Wind × Precip
PM2.5 at 8.9 µg/m³, PM10 at 10.3 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.86
- Wind
- breezy
- 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
- 4:57 AM
- Moonset
- 3:08 PM
- In sign
- ♒︎ Aquarius
Fireflies pulse through the magnolias
Carlinville at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: April 12 (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 — Carlinville
SPC has placed Carlinville 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 | 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
Carlinville's warmest month is July (~76°F mean) and its coldest is January (~28°F). Rainfall peaks in April (4.7 inches) and bottoms out in February (2.1 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 28° | 2.3″ | 5 |
| February | 32° | 2.1″ | 4 |
| March | 42° | 2.9″ | 6 |
| April | 54° | 4.7″ | 8 |
| May | 64° | 4.3″ | 8 |
| June | 73° | 4.6″ | 6 |
| July | 76° | 3.4″ | 6 |
| August | 74° | 3.2″ | 5 |
| September | 67° | 3.3″ | 5 |
| October | 55° | 3.3″ | 6 |
| November | 43° | 3.5″ | 5 |
| December | 33° | 2.3″ | 5 |
Regional context
Carlinville's baseline climate, derived from NOAA NCEI 1991-2020 normals at the nearest reporting station, swings from a January mean of 28°F to a July mean of 76°F — a 48°F seasonal arc typical of the mid-latitude bands. Annual precipitation runs about 40 inches spread across roughly 68 days with measurable rain or snow each year.
Precipitation runs summer-dominant here: April averages 4.7 inches across 7.7 days with measurable rain, driven mostly by warm-season storms and thunderstorm activity, while February drops to just 2.1 inches across 4.4 rainy days under drier cool-season air. The warm-season-wet rhythm lines Carlinville up with places like Standard City, IL, Nilwood, IL and Hettick, IL, where the May-September stretch delivers the bulk of the year's precipitation.
The frost-sensitive growing window opens around mid-April, when overnight lows reliably clear freezing for cool-season crops like kale, peas, spinach, and parsnips. Heat-loving transplants like tomatoes, peppers, and squash generally hold off for another 10-14 days to clear the last spring frost risk window. The window closes around mid-November, when overnight lows resume dipping below freezing and frost-tender plants need protection or harvest. Those dates are 30-year averages; the actual frost-free window in a given year can vary by 10-14 days at either end. Neighborhood-scale variation in elevation and cold-air pooling means the practical last-frost date inside Carlinville can lag the regional mean by 5-10 days in low spots, and a bench position with good cold-air drainage can run a week ahead.
Similar climates: Standard City, IL, Nilwood, IL, Hettick, IL, East Gillespie, IL, Chesterfield, IL.
Frequently asked
- When does it freeze in Carlinville?
- Carlinville's last spring frost typically falls around mid-April, and the first fall frost arrives around mid-November.
- What is the rainy season in Carlinville?
- April is the wettest month with about 4.7 inches of rain on average; the city receives roughly 40 inches annually.
- What is the warmest month in Carlinville?
- July is typically warmest, averaging about 76°F.
- What is the coldest month in Carlinville?
- January is typically coldest, averaging about 28°F.
- When can I start a vegetable garden in Carlinville?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-April); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Carlinville get?
- Carlinville averages about 68 rainy days per year.
- What hardiness zone is Carlinville?
- Carlinville'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
Carlinville, Illinois sits in a humid subtropical climate zone. January means hover near 28°F while July averages 76°F — a 48°F seasonal swing.
Across the year, Carlinville receives about 40 inches of precipitation spread over roughly 68 rainy days.
The rhythm of the year is set by latitude (39.3°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.