Naperville, Illinois climate: NOAA's gridded normals for the city, beside the nearest station records

NOAA's gridded 1991-2020 normals put Naperville's center at January lows of 16°F and July highs of 84°F, a yearly mean of 50.1°F and 38.6 inches of precipitation. No NOAA station keeps a record under the city's name. The nearest station record, Lisle (6 miles NE, 680 ft), has January lows of 15°F and July highs of 84°F.

153,124 people (Census Bureau 2024). Distances and directions are from the city's center.

  1. Jan 31° 16°
  2. Feb 36° 19°
  3. Mar 47° 28°
  4. Apr 60° 38°
  5. May 71° 49°
  6. Jun 81° 59°
  7. Jul 84° 64°
  8. Aug 82° 62°
  9. Sep 76° 54°
  10. Oct 63° 42°
  11. Nov 49° 31°
  12. Dec 36° 22°

Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.

The months above are NOAA's gridded normals at Naperville's center.

What is each month like in Naperville?

NOAA's grid estimates the normals every 5 km or so from the stations around each point, terrain included. It smooths between stations, so night lows at the heart of a large city can run warmer than the grid shows: at five big-city airports we compared, the grid's highs were within about 1°F of the station and its lows 1-6°F cooler. The nearest record's high and low are beside each month.

Naperville: NOAA gridded 1991-2020 normals by month, and the nearest record (Lisle) (°F, inches)
MonthHighLowMeanPrecip.Lisle highLisle low
January31°F16°F23.4°F2.0032°F15°F
February36°F19°F27.3°F1.8035°F18°F
March47°F28°F37.9°F2.3347°F26°F
April60°F38°F49.2°F3.8959°F36°F
May71°F49°F60.1°F4.5771°F47°F
June81°F59°F69.9°F4.4681°F58°F
July84°F64°F74.0°F3.9384°F62°F
August82°F62°F72.2°F4.0983°F60°F
September76°F54°F65.1°F3.2376°F52°F
October63°F42°F52.8°F3.4663°F40°F
November49°F31°F39.9°F2.6248°F30°F
December36°F22°F28.9°F2.1637°F21°F
Naperville: normal daily high and low by month (NOAA gridded normals)

In metric: a yearly mean of 10.1°C, January lows of −9°C, July highs of 29°C and 979 mm of precipitation a year.

Source: NOAA NCEI U.S. Monthly Gridded Climate Normals 1991-2020 (nClimGrid, accession 0245564); NOAA NCEI 1991-2020 station normals. The grid cell holding the city's Census center point.

What do the station records around Naperville say?

Each row is a NOAA station's own 1991-2020 normals, with the snow and frost dates the grid does not give. A record downhill or nearer the coast than the city can run warmer, one uphill cooler: compare the elevations.

The nearest NOAA station records to Naperville: 1991-2020 normals (°F, inches)
RecordWhereElevationYearJan lowJul highPrecip.SnowLast frost
LisleLisle-Morton Arboretum6 mi NE680 ft49.2°F15°F84°F40.2–April 28
Aurora8 mi W660 ft50.2°F16°F84°F39.528April 19

Source: NOAA NCEI 1991-2020 U.S. Climate Normals; place center and population: Census Bureau 2024. Last frost: the median last spring date of 32°F.

How much snow, how late a frost, what zone and how much sun in Naperville?

NOAA's grid gives no snow, frost dates or records, so these come from the nearest station record, Lisle (6 miles NE, 680 ft). NOAA publishes no snowfall normal for it; the nearest record that has one, Aurora (8 miles W), gets 28 inches a year. The last spring frost (32°F) comes after April 28 in half of years and the first autumn frost before October 16. Its record high is 105°F (1940) and its record low −26°F (1985) (kept since 1895).

The USDA's 2023 Plant Hardiness Zone Map puts Naperville in zones 5b to 6a across its 4 ZIP code areas.

Over a year 73% of the sunlight that would reach the ground under clear skies gets through the clouds in the area (3.9 kWh per square metre a day, NASA POWER 2001-2020); July is the sunniest month (81%) and January the cloudiest (61%).

Lisle's page has its months, frost probabilities, records by month and recent years. NOAA's grid has monthly figures only, so there are no day-by-day month pages for Naperville; the nearest record's month pages have them.

Source: NOAA NCEI 1991-2020 normals, station USC00115097; records: ACIS; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; sunshine: NASA POWER.

How does the climate vary across Naperville, ZIP code by ZIP code?

4 ZIP code areas lie wholly or partly in Naperville. On NOAA's grid 60564 is the warmest (50.2°F a year) and 60563 the coolest (49.9°F), so the city is nearly uniform. Each row also names the nearest station record and its frost dates.

Naperville ZIP code areas: USDA 2023 hardiness zone, NOAA gridded normals and the nearest station record
ZIP codeZoneYearJan lowJul highPrecip.Nearest recordLast frostFirst frost
605405b49.9°F16°F84°F38.6Lisle (5 mi)April 28October 16
605635b49.9°F16°F84°F38.3Aurora (5 mi)April 19October 23
605645b50.2°F16°F84°F38.5Aurora (8 mi)April 19October 23
605656a50.0°F16°F84°F38.9Lisle (6 mi)April 28October 16

Source: Census Bureau 2020 ZCTA-to-place relationship file and ZCTA centers; NOAA NCEI gridded and station normals, 1991-2020. A ZIP area counts when at least a tenth of its land (and 0.5 km²) is in the city; its figures are the grid cell at its center; frost dates are the nearest record's medians of 32°F.

Where next: each record in full, the state and the frost tool