Last Day of Spring Frost in Boulder
Frost is defined here as the minimum temperature being less than or equal to 32 F. Frost may occur even when the official temperature is above 32F as the ground can be colder than where the thermometer is located (typically 3 meters above the surface).Data from 1948-2018
earliest day of last frost: Apr 3 (2012) latest day: Jun 3 (1951) average: May 5 median May 3 standard deviation 11.6 days
Data from 1897-2018
earliest day of last frost: Apr 3 (2012) latest day: Jun 3 (1951) average: May 5 median May 3 standard deviation 11.6 days
