Naperville, Illinois Weather
Day 93 of summer. Read today’s microseason across nine climate regions →
Naperville weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 9:20 AM CDT · Open-Meteo
- TodaySep 21Overcast14%—63°59°—
- TuesdaySep 22Overcast11%—60°53°-3°
- WednesdaySep 23Overcast——63°56°+3°
- ThursdaySep 24Overcast——71°58°+8°
- FridaySep 25Overcast——63°60°-8°
- SaturdaySep 26Light Drizzle—0.13″60°54°-3°
- SundaySep 27Overcast14%—74°56°+14°
Air quality now AQI 31 · Good
AQI 31 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 4.8 µg/m³, PM10 at 4.9 µg/m³ — typical background levels with no transport signature.
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 4.8 µg/m³, PM10 at 4.9 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.98
- 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).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:31 PM
- Moonset
- 1:07 AM
- In sign
- ♑︎ Capricorn
Naperville at a glance
- Today vs. normal: Today averages 61°F (high 63°F, low 59°F), 4°F below the 65°F normal for Sep 21
- Last frost: April 28 (1991–2020 median, NOAA station 11 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Naperville
- Mon63°59°14%
- Tue60°53°11%
- Wed63°56°3%
- Thu71°58°1%
- Fri63°60°0%
- Sat60°54°4%
- Sun74°56°14%
- Mon77°60°10%
- Tue70°62°23%
- Wed71°54°28%
- Thu67°56°12%
- Fri59°53°13%
- Sat78°58°20%
- Sun63°51°16%
- Mon55°43°16%
- Tue59°42°16%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Naperville
Interactive wind and temperature map centered on Naperville — it loads in your browser. Open the full weather map.
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 16) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Naperville
Naperville sits in DuPage County, where the year’s longest day runs 15h 13m of daylight and its shortest just 9h 8m — a swing of +6h 4m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Chicago, the state’s largest city, lies about 25 miles to the ENE. The nearest town Naperville tracks is Aurora, roughly 6 miles to the W.
Air quality in Naperville
Air quality in Naperville’s county has held roughly steady since 2020; its cleanest year on record was 2025 (median AQI 42). See the full air-quality history for Naperville.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| July | tomatoes, peppers, beans, squash, fall brassicas, carrots | lettuce, peas, spinach, beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, garlic |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | — | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
Naperville peaks at about 76°F in July and bottoms near 23°F in January; May brings the heaviest rain (4.3 inches) and January the least (1.7 inches).
| Month | Mean temp | Precip |
|---|---|---|
| January | 23° | 1.7″ |
| February | 26° | 1.9″ |
| March | 37° | 2.9″ |
| April | 50° | 3.8″ |
| May | 59° | 4.3″ |
| June | 70° | 4.0″ |
| July | 76° | 2.9″ |
| August | 75° | 3.1″ |
| September | 67° | 3.1″ |
| October | 55° | 2.9″ |
| November | 40° | 3.0″ |
| December | 27° | 2.2″ |
Regional context
Similar climates Lisle, IL, Warrenville, IL, Bolingbrook, IL
Per modelled 1991-2020 normals (EC_Earth3P_HR model via Open-Meteo), Naperville runs from a 23°F January mean to 76°F in July, a 53°F seasonal spread, with near 35.8 inches of precipitation.
Precipitation in Naperville runs summer-dominant: May averages 4.3 inches from warm-season storms, while January drops to 1.7 inches under drier cool air. That puts Naperville in a summer-convective cohort with places like Lisle, IL, Warrenville, IL and Bolingbrook, IL.
Around April 28, Naperville sheds its freezing nights — kale, peas, spinach, and parsnips go into Naperville's beds. Heat-demanding starts go out a fortnight on in Naperville, after the soil warms and cold snaps clear. The season ends by October 16 in Naperville, once hard frosts set back in. That date is a median: Naperville freezes sooner in half of years.
Similar climates: Lisle, IL, Warrenville, IL, Bolingbrook, IL, Woodridge, IL, Aurora, IL.
Frequently asked
- When does it freeze in Naperville?
- Naperville's last spring frost lands near April 28, and in Naperville the first fall frost follows around October 16.
- What is the rainy season in Naperville?
- Naperville sees its heaviest rain in May (around 4.3 inches), part of roughly 36 inches a year.
- What is the warmest month in Naperville?
- Naperville peaks in July, when the mean runs near 76°F.
- What is the coldest month in Naperville?
- January is Naperville's coldest month, averaging about 23°F.
- When can I start a vegetable garden in Naperville?
- Around April 28, start frost-hardy crops in Naperville; tomatoes and basil belong a fortnight later.
- What hardiness zone is Naperville?
- Since January in Naperville averages 23°F, Naperville's USDA zone follows that floor — confirm it by ZIP.
- What is the 10-day forecast for Naperville?
- Naperville's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Naperville?
- See this week's day-by-day rain chances for Naperville in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Naperville?
- Current conditions for Naperville and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Naperville forecast updated?
- The Naperville forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Naperville?
- Today's sunrise and sunset times for Naperville are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Naperville?
- The next few days in Naperville's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Naperville sits at 41.7°N; its climate zone is warm-summer humid continental (Köppen approximation).
ZIP codes in Naperville
- 60540
- 60563
- 60564
- 60565
- 60567