First and last freeze/frost dates for Denver, CO ,United StatesFirst and last freeze/frost dates for:
Detailed station data* follows:
Lakewood, CO (Jefferson county):
|Spring 32°||May 24||May 19||May 15||May 12||May 9||May 6||May 3||Apr 29||Apr 24|
|Spring 28°||May 17||May 10||May 6||May 2||Apr 29||Apr 25||Apr 21||Apr 17||Apr 11|
|Spring 24°||May 2||Apr 26||Apr 22||Apr 19||Apr 15||Apr 12||Apr 8||Apr 4||Mar 29|
|Fall 32°||Sep 18||Sep 22||Sep 26||Sep 28||Oct 1||Oct 4||Oct 6||Oct 10||Oct 14|
|Fall 28°||Sep 24||Sep 29||Oct 3||Oct 6||Oct 9||Oct 12||Oct 15||Oct 19||Oct 24|
|Fall 24°||Sep 30||Oct 7||Oct 12||Oct 16||Oct 20||Oct 24||Oct 28||Nov 1||Nov 7|
Boulder, CO (Boulder county):
|Spring 32°||May 14||May 10||May 8||May 6||May 4||May 2||Apr 30||Apr 27||Apr 24|
|Spring 28°||May 7||May 2||Apr 28||Apr 25||Apr 22||Apr 20||Apr 17||Apr 13||Apr 8|
|Spring 24°||Apr 26||Apr 21||Apr 17||Apr 13||Apr 10||Apr 7||Apr 3||Mar 30||Mar 25|
|Fall 32°||Sep 18||Sep 23||Sep 26||Sep 29||Oct 2||Oct 5||Oct 8||Oct 11||Oct 16|
|Fall 28°||Sep 23||Sep 29||Oct 4||Oct 8||Oct 11||Oct 15||Oct 19||Oct 23||Oct 30|
|Fall 24°||Oct 3||Oct 10||Oct 15||Oct 20||Oct 24||Oct 28||Nov 1||Nov 6||Nov 13|
Evergreen, CO (Jefferson county):
|Spring 32°||Jun 18||Jun 13||Jun 9||Jun 6||Jun 3||May 31||May 28||May 24||May 18|
|Spring 28°||Jun 2||May 28||May 24||May 21||May 18||May 15||May 11||May 7||May 2|
|Spring 24°||May 18||May 13||May 9||May 6||May 3||Apr 30||Apr 27||Apr 24||Apr 19|
|Fall 32°||Sep 4||Sep 8||Sep 11||Sep 14||Sep 16||Sep 19||Sep 21||Sep 24||Sep 28|
|Fall 28°||Sep 12||Sep 17||Sep 21||Sep 24||Sep 27||Sep 30||Oct 3||Oct 6||Oct 11|
|Fall 24°||Sep 20||Sep 25||Sep 28||Oct 1||Oct 4||Oct 6||Oct 9||Oct 12||Oct 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.