Climateby Month

Aurora, IL climate by month

NOAA 1991-2020 normals · 675 ft elevation · also covers Naperville

Summers in Aurora are warm and often humid; winters are cold and snowy. Highs peak at 84°F in July and fall to 31°F in January. Wet days are spread through the year, from about 8 to 13 a month. Normal snowfall is about 28 in a year. The most comfortable time to visit is May.

Warmest month
84°F
July normal high
Coldest month
16°F
January normal low
Wet days a year
116
39.5 in of precipitation
Snow a year
27.9 in
normal snowfall

How warm is Aurora?

Normal highs range from 31°F in January to 84°F in July.

0°20°40°60°80°100° January: normal high 31°F (-1°C), low 16°F (-9°C) 31° 16° February: normal high 35°F (2°C), low 20°F (-7°C) March: normal high 47°F (8°C), low 29°F (-2°C) April: normal high 60°F (16°C), low 39°F (4°C) May: normal high 71°F (22°C), low 50°F (10°C) June: normal high 81°F (27°C), low 60°F (16°C) July: normal high 84°F (29°C), low 65°F (18°C) 84° 65° August: normal high 82°F (28°C), low 63°F (17°C) September: normal high 76°F (24°C), low 55°F (13°C) October: normal high 63°F (17°C), low 43°F (6°C) November: normal high 48°F (9°C), low 32°F (0°C) December: normal high 36°F (2°C), low 22°F (-6°C) JFMAMJJASOND

Bars run from the normal low to the normal high for each month.

How rainy is Aurora?

May has the most wet days (about 13); the year brings about 39 in of precipitation.

January: 9 wet days February: 8 wet days 8 March: 10 wet days April: 12 wet days May: 13 wet days 13 June: 11 wet days July: 9 wet days August: 9 wet days September: 8 wet days October: 9 wet days November: 9 wet days December: 9 wet days JFMAMJJASOND

Wet day: at least 0.01 in of rain or melted snow, counted from daily records 1991-2020.

How much does it snow?

Normal snowfall is 27.9 in a year, most of it in January.

January: 9.1 in of snow 9.1 February: 7.9 in of snow March: 2.6 in of snow April: 0.6 in of snow May: 0.0 in of snow 0.0 June: 0.0 in of snow July: 0.0 in of snow August: 0.0 in of snow September: 0.0 in of snow October: 0.0 in of snow November: 1.3 in of snow December: 6.4 in of snow JFMAMJJASOND

How humid is Aurora?

Muggy days peak in July, at about 11 days.

January: 0 muggy days 0 February: 0 muggy days March: 0 muggy days April: 0 muggy days May: 1 muggy days June: 5 muggy days July: 11 muggy days 11 August: 10 muggy days September: 3 muggy days October: 0 muggy days November: 0 muggy days December: 0 muggy days JFMAMJJASOND

Muggy day: daily mean dew point of 65°F or higher, from hourly observations 1991-2020 at Chicago O'hare International Airport, 24 mi NE of the city center (the nearest airport with complete hourly records).

How much daylight?

Daylight ranges from about 9.2 hours in December to 15.2 hours in June.

January: 9.6 hours of daylight February: 10.6 hours of daylight March: 12.0 hours of daylight April: 13.4 hours of daylight May: 14.6 hours of daylight June: 15.2 hours of daylight 15.2 July: 14.9 hours of daylight August: 13.8 hours of daylight September: 12.5 hours of daylight October: 11.1 hours of daylight November: 9.8 hours of daylight December: 9.2 hours of daylight 9.2 JFMAMJJASOND
See all numbers
Monthly climate normals and day counts for Aurora, 1991-2020
MonthHighLowPrecip.Wet daysSnowMuggy daysDaylight
January 31°F16°F 1.9 in9 9.1 in 0 9.6 h
February 35°F20°F 1.8 in8 7.9 in 0 10.6 h
March 47°F29°F 2.4 in10 2.6 in 0 12.0 h
April 60°F39°F 4.0 in12 0.6 in 0 13.4 h
May 71°F50°F 4.9 in13 0.0 in 1 14.6 h
June 81°F60°F 4.5 in11 0.0 in 5 15.2 h
July 84°F65°F 4.2 in9 0.0 in 11 14.9 h
August 82°F63°F 3.9 in9 0.0 in 10 13.8 h
September 76°F55°F 3.4 in8 0.0 in 3 12.5 h
October 63°F43°F 3.7 in9 0.0 in 0 11.1 h
November 48°F32°F 2.7 in9 1.3 in 0 9.8 h
December 36°F22°F 2.2 in9 6.4 in 0 9.2 h

High and low: NOAA 1991-2020 normal daily high and low. Wet days: at least 0.01 in of rain or melted snow. Muggy days: daily mean dew point 65°F or higher.

Best months to visit Aurora

By our comfort score, the best month is May.

Comfort score by month (0-100) and its parts, in days per month
MonthScoreComfortableNotable rainHot or cold
Jan 260525
Feb 320419
Mar 46369
Apr 621081
May 721681
Jun 641184
Jul 57576
Aug 58773
Sep 671462
Oct 601260
Nov 41358
Dec 280521

Score = 40 × share of comfortable days + 25 × share of days without notable rain + 20 × share of days neither hot (90°F+) nor cold (high 40°F or below) + 15 × daylight. How the score works.

Frost dates in Aurora

The last spring frost typically comes around Apr 19, and the first fall frost around Oct 23, leaving 185 frost-free days in a typical year.

Frost and freeze dates for Aurora
Typical date1 year in 10
Last spring frost (32°F)Apr 19after May 4
First fall frost (32°F)Oct 23before Oct 9
Last hard freeze (28°F)Apr 8after Apr 23
First hard freeze (28°F)Nov 2before Oct 21
Frost-free season185 daysunder 164 days

"Typical" is the date with a 50% chance of a later spring frost (or earlier fall frost). Planting after the "1 year in 10" spring date gives a 90% chance of no further frost. The Old Farmer's Almanac publishes 30% dates, which fall between our typical and 1-in-10 dates.

Station: Aurora (USC00110338), NOAA 1991-2020 freeze probabilities. Frost dates for every city in Illinois.

Hottest and coldest readings, 1991-2020

The highest reading was 103°F (July 8, 2012); the lowest was -25°F (January 31, 2019).

From the temperature station's daily records with NOAA quality flags removed. Not an all-time record.

Near Aurora

Similar climates elsewhere

Also covers

Naperville uses the same temperature and rain stations as Aurora, so its monthly numbers are the ones on this page.

Where the numbers come from

  • Temperature, rain, snowfall, snow depth and frost dates: Aurora (USC00110338), 1.5 mi NNE of the city center, 660 ft . NOAA normals and daily records, 1991-2020.
  • Humidity and wind by hour: West Chicago Dupage Airport (USW00094892), 11 mi NNE of the city center, 754 ft (79 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: Chicago O'hare International Airport (725300-94846), 24 mi NE of the city center, 672 ft . Hourly observations, 1991-2020.
  • Not available for this location: cloud cover (no station close enough or similar enough in elevation).

Distances from the city center (USGS). Methodology · Report an error