Northbrook Illinois Climate Data

Monthly Average Climate Data for Northbrook Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January17.7 °F31.4 °F2.12 in.
February20.4 °F35.1 °F2.0 in.
March29.2 °F45.1 °F2.22 in.
April39.3 °F56.8 °F3.8 in.
May50.2 °F68.6 °F4.69 in.
June60.1 °F78.8 °F4.33 in.
July66.0 °F83.2 °F3.65 in.
August65.0 °F81.5 °F4.08 in.
September57.2 °F75.0 °F3.45 in.
October45.2 °F62.5 °F3.46 in.
November33.6 °F48.1 °F2.6 in.
December23.8 °F36.8 °F2.24 in.
Annual42.3 °F58.6 °F38.64 in.

Climate Data for Northbrook Illinois

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateMay 1 - May 10
Average Days With Frost100-125 Days
Plant Hardiness Zone - 2023Zone 6a : -10°F to -5°F
Plant Hardiness Zone - 2012Zone 5b : -15°F to -10°F
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation