First and last freeze/frost dates for Chicago, IL ,United StatesFirst and last freeze/frost dates for:
Detailed station data* follows:
Chicago Ohare Wso Ap, IL (Cook county):
|Spring 32°||May 10||May 5||May 1||Apr 28||Apr 25||Apr 22||Apr 19||Apr 15||Apr 10|
|Spring 28°||Apr 24||Apr 20||Apr 17||Apr 14||Apr 12||Apr 10||Apr 7||Apr 4||Mar 31|
|Spring 24°||Apr 15||Apr 11||Apr 8||Apr 6||Apr 3||Apr 1||Mar 29||Mar 26||Mar 22|
|Fall 32°||Sep 28||Oct 3||Oct 7||Oct 10||Oct 13||Oct 16||Oct 19||Oct 23||Oct 28|
|Fall 28°||Oct 8||Oct 14||Oct 19||Oct 23||Oct 26||Oct 30||Nov 2||Nov 6||Nov 13|
|Fall 24°||Oct 24||Oct 29||Nov 1||Nov 5||Nov 8||Nov 11||Nov 15||Nov 19||Nov 24|
Waukegan, IL (Lake county):
|Spring 32°||May 12||May 7||May 3||Apr 30||Apr 27||Apr 24||Apr 21||Apr 17||Apr 12|
|Spring 28°||Apr 27||Apr 23||Apr 20||Apr 17||Apr 15||Apr 13||Apr 10||Apr 7||Apr 3|
|Spring 24°||Apr 16||Apr 13||Apr 10||Apr 8||Apr 6||Apr 4||Apr 2||Mar 31||Mar 27|
|Fall 32°||Sep 28||Oct 4||Oct 8||Oct 12||Oct 15||Oct 18||Oct 22||Oct 26||Oct 31|
|Fall 28°||Oct 11||Oct 17||Oct 21||Oct 24||Oct 27||Oct 30||Nov 2||Nov 6||Nov 11|
|Fall 24°||Oct 24||Oct 29||Nov 1||Nov 4||Nov 7||Nov 10||Nov 13||Nov 17||Nov 22|
Barrington 1 Nw, IL (Lake county):
|Spring 32°||May 21||May 14||May 9||May 5||May 1||Apr 28||Apr 24||Apr 19||Apr 12|
|Spring 28°||May 6||May 1||Apr 27||Apr 23||Apr 20||Apr 17||Apr 13||Apr 9||Apr 4|
|Spring 24°||Apr 18||Apr 14||Apr 12||Apr 9||Apr 7||Apr 5||Apr 3||Mar 31||Mar 28|
|Fall 32°||Sep 25||Sep 30||Oct 3||Oct 6||Oct 9||Oct 11||Oct 14||Oct 18||Oct 22|
|Fall 28°||Oct 2||Oct 8||Oct 13||Oct 17||Oct 21||Oct 25||Oct 29||Nov 2||Nov 9|
|Fall 24°||Oct 16||Oct 22||Oct 26||Oct 30||Nov 1||Nov 4||Nov 8||Nov 12||Nov 17|
* This station data is available courtesy the National Climatic Data Center.
For each weather station, you will see a temperature along with tables of data organized into percentage columns. The percentage column tells you the probability that you will experience that row's temperature on or near that date. Here are two examples to help you determine your probable last frost and first freeze dates.
Example 1 (Last Frost). In the Spring 32° row, if you have "Apr 15" under the 50% column, that means you have a 50% chance of seeing frost on or before April 15th.
Example 2 (First Freeze). In the Fall 24° row, if you have "Dec 1" under the 90% column, that means you have a 90% chance of seeing 24 degrees on or after December 1st.
Empty cells indicate you have a less than 10% chance of ever seeing that temperature.